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Game 1 Unit 25 of 64 1 hr learning time

High Score Persistence

Adding high score tracking that persists across plays. Each song/difficulty combination tracks its own record, with celebration when records are broken.

39% of SID Symphony

“Beat your best.” Three words that drive replay. High scores transform a single playthrough into an ongoing challenge against yourself.

This unit adds high score tracking. Each song/difficulty combination stores its own record. Beat it, and “NEW HIGH SCORE!” celebrates your achievement.

Run It

Assemble and run:

acme -f cbm -o symphony.prg symphony.asm

Unit 25 Screenshot

Play any song to completion (or game over). The results screen now shows your high score for that song/difficulty. Beat it, and you’ll see the cyan “NEW HIGH SCORE!” message.

High score tracking — beat your best on each song and difficulty

High Score Table

We need to store 12 high scores: 4 songs × 3 difficulties. Each score is 16-bit (2 bytes), so:

; High Score Table (4 songs x 3 difficulties = 12 entries, 2 bytes each)
; Index = (song * 3) + difficulty

high_scores:
            ; Song 1 (First Steps)
            !word 0               ; Easy high score
            !word 0               ; Normal high score
            !word 0               ; Hard high score
            ; Song 2 (Upbeat Groove)
            !word 0               ; Easy
            !word 0               ; Normal
            !word 0               ; Hard
            ; Song 3 (Speed Rush)
            !word 0
            !word 0
            !word 0
            ; Song 4 (Off-Beat)
            !word 0
            !word 0
            !word 0

The !word 0 directive creates a 2-byte value initialised to zero. At startup, all high scores are 0—any score beats them.

Calculating the Table Index

To find the right high score, we calculate:

index = (selected_song × 3 + difficulty) × 2

In assembly:

check_high_score:
            ; Calculate table index: (selected_song * 3 + difficulty) * 2
            lda selected_song
            asl                     ; × 2
            clc
            adc selected_song       ; × 3
            clc
            adc difficulty          ; + difficulty
            asl                     ; × 2 (for 2-byte entries)
            tax                     ; X = table index

The multiply-by-3 uses a clever trick: × 2 + original = × 3. The final × 2 accounts for 2-byte entries.

Multi-Byte Score Comparison

Comparing 16-bit scores requires checking both bytes:

            ; Compare current score with high score
            ; First compare high bytes
            lda score_hi
            cmp high_scores+1,x     ; Compare high byte
            bcc hs_not_higher       ; Current < high
            bne hs_is_higher        ; Current > high

            ; High bytes equal, compare low bytes
            lda score_lo
            cmp high_scores,x       ; Compare low byte
            bcc hs_not_higher       ; Current < high
            beq hs_not_higher       ; Current = high

The comparison works like this:

  1. Compare high bytes first
  2. If current high byte is less, score is lower
  3. If current high byte is greater, score is higher
  4. If equal, compare low bytes

Updating the High Score

When we beat the record:

hs_is_higher:
            ; New high score! Update table
            lda score_lo
            sta high_scores,x
            lda score_hi
            sta high_scores+1,x

            ; Set flag
            lda #1
            sta new_high_score

The new_high_score flag tells the results screen to show the celebration message.

Display Logic

On the game over or results screen:

            ; Check if this was a new high score
            lda new_high_score
            beq draw_prev_high

            ; Draw "NEW HIGH SCORE!" in bright cyan
            ldx #0
draw_new_hs:
            lda new_hs_text,x
            bne +
            jmp go_draw_retry
+           sta SCREEN + (14 * 40) + 12,x
            lda #3                  ; Cyan
            sta COLRAM + (14 * 40) + 12,x
            inx
            jmp draw_new_hs

When you beat the high score, the message appears in cyan. Otherwise, we display the current high score in grey.

Branch Distance Limits

Notice the bne + / jmp pattern:

            lda new_hs_text,x
            bne +                   ; Branch over jump if not zero
            jmp go_draw_retry       ; Far jump when zero
+           sta SCREEN ...

The 6502’s beq instruction can only branch ±127 bytes. When targets are too far, we use a trampoline: branch over a jump instruction. This adds 3 bytes but handles any distance.

Memory Trade-offs

The high score table uses 24 bytes (12 × 2). We could reduce this by:

  • One global high score (2 bytes)
  • Per-song only, not per-difficulty (8 bytes)
  • Storing only top 3 scores globally (6 bytes)

But 24 bytes is trivial on a 64K machine, and per-song/difficulty tracking provides better motivation. Players can chase records on Easy while learning, then Hard for mastery.

Session vs. Persistent Storage

Our high scores persist during the session—reset the computer and they’re gone. True persistence would require:

  • Saving to tape (slow, requires user action)
  • Saving to disk (fast, but not all C64s have drives)
  • Battery-backed RAM (expensive, rare)

For an educational game, session persistence is sufficient. Players can set records within a play session without the complexity of file I/O.

Why High Scores Matter

High scores provide:

  1. Replay motivation - “One more try to beat my record”
  2. Skill measurement - Concrete feedback on improvement
  3. Per-variant goals - Different challenges for different modes
  4. Session narrative - Building towards mastery over time

Without high scores, once you complete a song, there’s no reason to replay. With them, every play is an opportunity to improve.

The Complete Code

; ============================================================================
; SID SYMPHONY - Unit 25: High Score Persistence
; ============================================================================
; Adding high score tracking that persists across plays within a session.
; Each song/difficulty combination tracks its own high score. Beating a high
; score triggers a "NEW HIGH SCORE" celebration.
;
; New concepts: Score comparison, multi-byte arithmetic, high score tables
;
; Controls: Z = Track 1, X = Track 2, C = Track 3
;           Up/Down = Song selection, Left/Right = Difficulty
;           P = Toggle practice mode, +/- = Speed adjustment
;           Fire/Space = Start game
; ============================================================================

; ============================================================================
; CUSTOMISATION SECTION
; ============================================================================

; Screenshot mode - set to 1 to skip title and show menu immediately
; Used for automated screenshot capture. Override with: acme -DSCREENSHOT_MODE=1
!ifndef SCREENSHOT_MODE { SCREENSHOT_MODE = 0 }

; SID Voice Settings (for note playback)
VOICE1_WAVE = $21               ; Sawtooth for track 1
VOICE2_WAVE = $41               ; Pulse for track 2
VOICE3_WAVE = $11               ; Triangle for track 3

VOICE1_FREQ = $1C
VOICE2_FREQ = $0E
VOICE3_FREQ = $07

VOICE_AD    = $09               ; Attack=0, Decay=9
VOICE_SR    = $00               ; Sustain=0, Release=0
PULSE_WIDTH = $08

; Perfect hit sound - bright and satisfying
PERFECT_SFX_FREQ  = $30         ; Higher pitch
PERFECT_SFX_WAVE  = $21         ; Sawtooth (bright)
PERFECT_SFX_AD    = $08         ; Fast attack, medium decay
PERFECT_SFX_SR    = $00         ; No sustain

; Good hit sound - positive but lesser
GOOD_SFX_FREQ     = $20         ; Lower pitch than perfect
GOOD_SFX_WAVE     = $11         ; Triangle (softer)
GOOD_SFX_AD       = $0A         ; Slightly slower decay
GOOD_SFX_SR       = $00         ; No sustain

; Miss sound settings - harsh buzz
MISS_FREQ   = $08
MISS_WAVE   = $81               ; Noise
MISS_AD     = $00               ; Instant attack
MISS_SR     = $A0               ; Quick sustain, fast release

; Menu sound settings
MENU_SELECT_FREQ  = $18         ; Menu click pitch
MENU_SELECT_WAVE  = $41         ; Pulse for click
MENU_SELECT_AD    = $00         ; Instant
MENU_SELECT_SR    = $80         ; Very short

MENU_MOVE_FREQ    = $10         ; Lower pitch for cursor move
MENU_MOVE_WAVE    = $11         ; Triangle (soft)
MENU_MOVE_AD      = $00         ; Instant
MENU_MOVE_SR      = $40         ; Very short

; Visual Settings
BORDER_COL  = 0
BG_COL      = 0

TRACK1_NOTE_COL = 10            ; Light red for high track
TRACK2_NOTE_COL = 13            ; Light green for mid track
TRACK3_NOTE_COL = 14            ; Light blue for low track

TRACK_LINE_COL = 11             ; Grey for track lines
HIT_ZONE_COL = 7                ; Yellow for hit zone

HIT_COL     = 1
PERFECT_COL = 1                 ; White flash for perfect
GOOD_COL    = 7                 ; Yellow flash for good
MISS_COL    = 2                 ; Red flash for miss

HEALTH_COL  = 5                 ; Green for health bar
PROGRESS_COL = 3                ; Cyan for progress bar
COMBO_COL   = 13                ; Light green for combo

; Title screen colours
TITLE_COL   = 1                 ; White for title
SUBTITLE_COL = 11               ; Grey for subtitle
MENU_COL    = 7                 ; Yellow for menu items
CURSOR_COL  = 1                 ; White for cursor
EASY_COL    = 5                 ; Green for Easy
NORMAL_COL  = 7                 ; Yellow for Normal
HARD_COL    = 2                 ; Red for Hard

; ============================================================================
; SCORING SETTINGS (BALANCED)
; ============================================================================

PERFECT_SCORE = 100             ; Perfect hit value
GOOD_SCORE    = 50              ; Good hit value

; ============================================================================
; COMBO SETTINGS (BALANCED)
; ============================================================================

COMBO_TIER_2  = 10              ; 2x multiplier at 10 hits
COMBO_TIER_3  = 25              ; 3x multiplier at 25 hits
COMBO_TIER_4  = 50              ; 4x multiplier at 50 hits

; Combo border colours (escalating intensity)
COMBO_BORDER_0 = 0              ; Black - no combo
COMBO_BORDER_1 = 11             ; Dark grey - building
COMBO_BORDER_2 = 5              ; Green - 2x (tier 2)
COMBO_BORDER_3 = 7              ; Yellow - 3x (tier 3)
COMBO_BORDER_4 = 2              ; Red - 4x (tier 4 / fire!)

; ============================================================================
; HEALTH SETTINGS (BASE VALUES - MODIFIED BY DIFFICULTY)
; ============================================================================

HEALTH_MAX    = 64              ; Maximum health
HEALTH_START  = 32              ; Start at half health
HEALTH_PERFECT = 4              ; Gain 4 for perfect
HEALTH_GOOD   = 2               ; Gain 2 for good

; Health loss per difficulty
HEALTH_MISS_EASY   = 4          ; Forgiving
HEALTH_MISS_NORMAL = 8          ; Balanced
HEALTH_MISS_HARD   = 12         ; Punishing

; ============================================================================
; HIT DETECTION SETTINGS (BASE - MODIFIED BY DIFFICULTY)
; ============================================================================

; Hit zone column range (where notes can be hit)
HIT_ZONE_START = 2              ; Leftmost hittable column
HIT_ZONE_END   = 6              ; Rightmost hittable column

; Perfect timing column (centre of hit zone)
PERFECT_COL_POS = 4

; Timing windows per difficulty (columns from perfect)
; Easy: Perfect ±2, Good ±4
; Normal: Perfect ±1, Good ±2
; Hard: Perfect ±0, Good ±1

PERFECT_WINDOW_EASY   = 2
PERFECT_WINDOW_NORMAL = 1
PERFECT_WINDOW_HARD   = 0

GOOD_WINDOW_EASY      = 4
GOOD_WINDOW_NORMAL    = 2
GOOD_WINDOW_HARD      = 1

; ============================================================================
; DIFFICULTY SETTINGS
; ============================================================================

DIFF_EASY   = 0
DIFF_NORMAL = 1
DIFF_HARD   = 2

; ============================================================================
; SONG SETTINGS
; ============================================================================

PROGRESS_WIDTH = 16             ; Progress bar width

; Per-song tempo (frames per beat)
TEMPO_SONG1   = 25              ; 120 BPM
TEMPO_SONG2   = 23              ; 130 BPM
TEMPO_SONG3   = 20              ; 150 BPM
TEMPO_SONG4   = 24              ; 125 BPM (syncopated feel)

; Per-song length (beats)
LENGTH_SONG1  = 64
LENGTH_SONG2  = 64
LENGTH_SONG3  = 64
LENGTH_SONG4  = 64

; ============================================================================
; MENU SETTINGS
; ============================================================================

NUM_SONGS     = 4
KEY_DELAY     = 10              ; Frames between key repeats

; ============================================================================
; PRACTICE MODE SETTINGS
; ============================================================================

; Speed multipliers (stored as frame adjustment)
; Higher value = slower (more frames per beat)
SPEED_HALF    = 2               ; 0.5x speed (double frames)
SPEED_3QRTR   = 1               ; 0.75x speed (4/3 frames, approx +1)
SPEED_NORMAL  = 0               ; 1.0x speed (no adjustment)

NUM_SPEEDS    = 3

PRACTICE_COL  = 3               ; Cyan for practice mode indicator

; ============================================================================
; GAME STATES
; ============================================================================

STATE_TITLE   = 0               ; Title screen
STATE_MENU    = 1               ; Song selection menu
STATE_PLAYING = 2               ; Gameplay
STATE_RESULTS = 3               ; Success results
STATE_GAMEOVER = 4              ; Failure game over

; ============================================================================
; MEMORY MAP
; ============================================================================

SCREEN      = $0400
COLRAM      = $D800
BORDER      = $D020
BGCOL       = $D021
CHARPTR     = $D018

CHARSET     = $3000

; SID registers
SID         = $D400
SID_V1_FREQ_LO = $D400
SID_V1_FREQ_HI = $D401
SID_V1_PWHI = $D403
SID_V1_CTRL = $D404
SID_V1_AD   = $D405
SID_V1_SR   = $D406

SID_V2_FREQ_LO = $D407
SID_V2_FREQ_HI = $D408
SID_V2_PWHI = $D40A
SID_V2_CTRL = $D40B
SID_V2_AD   = $D40C
SID_V2_SR   = $D40D

SID_V3_FREQ_LO = $D40E
SID_V3_FREQ_HI = $D40F
SID_V3_PWHI = $D411
SID_V3_CTRL = $D412
SID_V3_AD   = $D413
SID_V3_SR   = $D414

SID_VOLUME  = $D418

; CIA keyboard and joystick
CIA1_PRA    = $DC00
CIA1_PRB    = $DC01

; Track positions (balanced spacing)
TRACK1_ROW  = 8                 ; High track
TRACK2_ROW  = 12                ; Mid track
TRACK3_ROW  = 16                ; Low track

; HUD positions
HEALTH_ROW  = 23                ; Health bar row
PROGRESS_ROW = 24               ; Progress bar row

; Combo display position
COMBO_ROW   = 2                 ; Combo display row

; Hit zone
HIT_ZONE_COLUMN = 3             ; Where notes are hit (visual)

; Custom character codes
CHAR_NOTE   = 128
CHAR_TRACK  = 129
CHAR_HITZONE = 130
CHAR_SPACE  = 32
CHAR_BAR_FULL = 131
CHAR_BAR_EMPTY = 132
CHAR_CURSOR = 62                ; > character for menu cursor
CHAR_ARROW_L = 60               ; < for difficulty
CHAR_ARROW_R = 62               ; > for difficulty

; Note settings
MAX_NOTES   = 8                 ; Maximum simultaneous notes
NOTE_SPAWN_COL = 37             ; Where notes appear

; Timing
END_DELAY_FRAMES = 75           ; 1.5 seconds after song ends

; Zero page
ZP_PTR      = $FB
ZP_PTR_HI   = $FC

; Variables
frame_count = $02
beat_count  = $03
song_pos    = $04
song_pos_hi = $05
temp_track  = $06
key_pressed = $07
hit_quality = $08
border_flash = $09
miss_track  = $0A
game_state  = $0B
hit_note_freq = $0C
song_beat   = $0D
song_ended  = $0E
end_delay   = $0F
cursor_pos  = $10               ; Menu cursor position
key_delay_count = $11           ; Key repeat delay counter
selected_song = $12             ; Which song to play
frames_per_beat = $13           ; Current song's tempo
song_length = $14               ; Current song's length
difficulty  = $15               ; 0=Easy, 1=Normal, 2=Hard
perfect_window = $16            ; Current perfect timing window
good_window = $17               ; Current good timing window
health_miss_amt = $18           ; Health loss on miss
practice_mode = $19             ; 0=Normal play, 1=Practice mode (NEW!)
speed_setting = $1A             ; 0=0.5x, 1=0.75x, 2=1.0x (NEW!)

; ----------------------------------------------------------------------------
; BASIC Stub
; ----------------------------------------------------------------------------

            * = $0801

            !byte $0C, $08
            !byte $0A, $00
            !byte $9E
            !text "2064"
            !byte $00
            !byte $00, $00

; ----------------------------------------------------------------------------
; Main Program
; ----------------------------------------------------------------------------

            * = $0810

start:
            jsr copy_charset
            jsr init_sid

            ; Start with Normal difficulty
            lda #DIFF_NORMAL
            sta difficulty

            ; Practice mode off, normal speed
            lda #0
            sta practice_mode
            lda #NUM_SPEEDS-1       ; Start at 1.0x (normal speed)
            sta speed_setting

!if SCREENSHOT_MODE = 1 {
            ; Screenshot mode: skip title, go to menu
            jsr show_menu
            lda #STATE_MENU
            sta game_state
} else {
            ; Normal mode: show title screen
            jsr show_title
            lda #STATE_TITLE
            sta game_state
}

main_loop:
            lda #$FF
wait_raster:
            cmp $D012
            bne wait_raster

            lda game_state
            cmp #STATE_TITLE
            beq do_title
            cmp #STATE_MENU
            beq do_menu
            cmp #STATE_PLAYING
            beq do_playing
            cmp #STATE_RESULTS
            beq do_results
            jmp do_gameover

do_title:
            jsr update_title
            jmp main_loop

do_menu:
            jsr update_menu
            jmp main_loop

do_playing:
            jsr update_playing
            jmp main_loop

do_results:
            jsr update_results
            jmp main_loop

do_gameover:
            jsr update_gameover
            jmp main_loop

; ----------------------------------------------------------------------------
; Show Title Screen
; ----------------------------------------------------------------------------

show_title:
            ; Clear screen
            lda #BORDER_COL
            sta BORDER
            lda #BG_COL
            sta BGCOL

            ldx #0
            lda #CHAR_SPACE
clear_title:
            sta SCREEN,x
            sta SCREEN+$100,x
            sta SCREEN+$200,x
            sta SCREEN+$2E8,x
            inx
            bne clear_title

            ; Draw big title "SID SYMPHONY"
            ldx #0
draw_title_text:
            lda title_big,x
            beq draw_title_done
            sta SCREEN + (8 * 40) + 14,x
            lda #TITLE_COL
            sta COLRAM + (8 * 40) + 14,x
            inx
            jmp draw_title_text
draw_title_done:

            ; Draw subtitle "A RHYTHM GAME"
            ldx #0
draw_subtitle:
            lda subtitle_text,x
            beq draw_subtitle_done
            sta SCREEN + (10 * 40) + 13,x
            lda #SUBTITLE_COL
            sta COLRAM + (10 * 40) + 13,x
            inx
            jmp draw_subtitle
draw_subtitle_done:

            ; Draw controls
            ldx #0
draw_controls:
            lda controls_text,x
            beq draw_controls_done
            sta SCREEN + (14 * 40) + 11,x
            lda #11
            sta COLRAM + (14 * 40) + 11,x
            inx
            jmp draw_controls
draw_controls_done:

            ; Draw track info
            ldx #0
draw_track_info:
            lda track_info,x
            beq draw_track_done
            sta SCREEN + (16 * 40) + 9,x
            lda #11
            sta COLRAM + (16 * 40) + 9,x
            inx
            jmp draw_track_info
draw_track_done:

            ; Draw "PRESS FIRE TO START"
            ldx #0
draw_press_fire:
            lda press_fire_text,x
            beq draw_press_done
            sta SCREEN + (20 * 40) + 10,x
            lda #7              ; Yellow
            sta COLRAM + (20 * 40) + 10,x
            inx
            jmp draw_press_fire
draw_press_done:

            rts

title_big:
            !scr "sid symphony"
            !byte 0

subtitle_text:
            !scr "a rhythm game"
            !byte 0

controls_text:
            !scr "controls: z / x / c"
            !byte 0

track_info:
            !scr "hit notes as they reach"
            !byte 0

press_fire_text:
            !scr "press fire to start"
            !byte 0

; ----------------------------------------------------------------------------
; Update Title State
; ----------------------------------------------------------------------------

update_title:
            ; Check for fire button (joystick port 2)
            lda CIA1_PRA
            and #$10            ; Bit 4 = fire
            beq title_fire_pressed

            ; Also check space bar as alternative
            lda #$7F
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10            ; Space
            beq title_fire_pressed

            ; No input - stay on title
            lda #$FF
            sta CIA1_PRA
            rts

title_fire_pressed:
            lda #$FF
            sta CIA1_PRA

            ; Play menu select sound
            jsr play_menu_select

            ; Go to song selection menu
            jsr show_menu
            lda #STATE_MENU
            sta game_state
            rts

; ----------------------------------------------------------------------------
; Show Song Selection Menu
; ----------------------------------------------------------------------------

show_menu:
            ; Clear screen
            ldx #0
            lda #CHAR_SPACE
clear_menu:
            sta SCREEN,x
            sta SCREEN+$100,x
            sta SCREEN+$200,x
            sta SCREEN+$2E8,x
            inx
            bne clear_menu

            ; Initialise cursor
            lda #0
            sta cursor_pos
            sta key_delay_count

            ; Draw menu title
            ldx #0
draw_menu_title:
            lda menu_title,x
            beq draw_menu_title_done
            sta SCREEN + (3 * 40) + 12,x
            lda #TITLE_COL
            sta COLRAM + (3 * 40) + 12,x
            inx
            jmp draw_menu_title
draw_menu_title_done:

            ; Draw song list
            jsr draw_song_list

            ; Draw difficulty section
            jsr draw_difficulty

            ; Draw practice mode section
            jsr draw_practice_mode

            ; Draw instructions
            ldx #0
draw_menu_instr:
            lda menu_instructions,x
            beq draw_menu_instr_done
            sta SCREEN + (21 * 40) + 1,x
            lda #SUBTITLE_COL
            sta COLRAM + (21 * 40) + 1,x
            inx
            jmp draw_menu_instr
draw_menu_instr_done:

            ; Draw practice instructions
            ldx #0
draw_prac_instr:
            lda practice_instructions,x
            beq draw_prac_instr_done
            sta SCREEN + (22 * 40) + 5,x
            lda #SUBTITLE_COL
            sta COLRAM + (22 * 40) + 5,x
            inx
            jmp draw_prac_instr
draw_prac_instr_done:

            rts

menu_title:
            !scr "select a song"
            !byte 0

menu_instructions:
            !scr "up/down:song  left/right:difficulty"
            !byte 0

practice_instructions:
            !scr "p:practice  +/-:speed"
            !byte 0

; ----------------------------------------------------------------------------
; Draw Song List
; ----------------------------------------------------------------------------

draw_song_list:
            ; Song 1: "First Steps" (120 BPM)
            ldx #0
draw_song1:
            lda song1_name,x
            beq draw_song1_done
            sta SCREEN + (8 * 40) + 14,x
            lda #MENU_COL
            sta COLRAM + (8 * 40) + 14,x
            inx
            jmp draw_song1
draw_song1_done:

            ; Song 1 tempo info
            ldx #0
draw_tempo1:
            lda song1_tempo_text,x
            beq draw_tempo1_done
            sta SCREEN + (8 * 40) + 27,x
            lda #SUBTITLE_COL
            sta COLRAM + (8 * 40) + 27,x
            inx
            jmp draw_tempo1
draw_tempo1_done:

            ; Song 2: "Upbeat Groove" (130 BPM)
            ldx #0
draw_song2:
            lda song2_name,x
            beq draw_song2_done
            sta SCREEN + (10 * 40) + 14,x
            lda #MENU_COL
            sta COLRAM + (10 * 40) + 14,x
            inx
            jmp draw_song2
draw_song2_done:

            ; Song 2 tempo info
            ldx #0
draw_tempo2:
            lda song2_tempo_text,x
            beq draw_tempo2_done
            sta SCREEN + (10 * 40) + 27,x
            lda #SUBTITLE_COL
            sta COLRAM + (10 * 40) + 27,x
            inx
            jmp draw_tempo2
draw_tempo2_done:

            ; Song 3: "Speed Rush" (150 BPM)
            ldx #0
draw_song3:
            lda song3_name,x
            beq draw_song3_done
            sta SCREEN + (12 * 40) + 14,x
            lda #MENU_COL
            sta COLRAM + (12 * 40) + 14,x
            inx
            jmp draw_song3
draw_song3_done:

            ; Song 3 tempo info
            ldx #0
draw_tempo3:
            lda song3_tempo_text,x
            beq draw_tempo3_done
            sta SCREEN + (12 * 40) + 27,x
            lda #SUBTITLE_COL
            sta COLRAM + (12 * 40) + 27,x
            inx
            jmp draw_tempo3
draw_tempo3_done:

            ; Song 4: "Off-Beat" (125 BPM)
            ldx #0
draw_song4:
            lda song4_name,x
            beq draw_song4_done
            sta SCREEN + (14 * 40) + 14,x
            lda #MENU_COL
            sta COLRAM + (14 * 40) + 14,x
            inx
            jmp draw_song4
draw_song4_done:

            ; Song 4 tempo info
            ldx #0
draw_tempo4:
            lda song4_tempo_text,x
            beq draw_tempo4_done
            sta SCREEN + (14 * 40) + 27,x
            lda #SUBTITLE_COL
            sta COLRAM + (14 * 40) + 27,x
            inx
            jmp draw_tempo4
draw_tempo4_done:

            ; Draw cursor at current position
            jsr draw_cursor
            rts

; Song names and info
song1_name:
            !scr "first steps"
            !byte 0

song1_tempo_text:
            !scr "(120 bpm)"
            !byte 0

song2_name:
            !scr "upbeat groove"
            !byte 0

song2_tempo_text:
            !scr "(130 bpm)"
            !byte 0

song3_name:
            !scr "speed rush"
            !byte 0

song3_tempo_text:
            !scr "(150 bpm)"
            !byte 0

song4_name:
            !scr "off-beat"
            !byte 0

song4_tempo_text:
            !scr "(125 bpm)"
            !byte 0

; ----------------------------------------------------------------------------
; Draw Difficulty Selection
; ----------------------------------------------------------------------------

draw_difficulty:
            ; Draw "DIFFICULTY:" label
            ldx #0
draw_diff_label:
            lda diff_label,x
            beq draw_diff_label_done
            sta SCREEN + (15 * 40) + 10,x
            lda #TITLE_COL
            sta COLRAM + (15 * 40) + 10,x
            inx
            jmp draw_diff_label
draw_diff_label_done:

            ; Draw arrows
            lda #CHAR_ARROW_L
            sta SCREEN + (15 * 40) + 22
            lda #SUBTITLE_COL
            sta COLRAM + (15 * 40) + 22

            lda #CHAR_ARROW_R
            sta SCREEN + (15 * 40) + 30
            lda #SUBTITLE_COL
            sta COLRAM + (15 * 40) + 30

            ; Draw current difficulty
            jsr draw_current_difficulty

            rts

diff_label:
            !scr "difficulty:"
            !byte 0

; ----------------------------------------------------------------------------
; Draw Current Difficulty Name
; ----------------------------------------------------------------------------

draw_current_difficulty:
            ; Clear difficulty name area
            lda #CHAR_SPACE
            sta SCREEN + (15 * 40) + 24
            sta SCREEN + (15 * 40) + 25
            sta SCREEN + (15 * 40) + 26
            sta SCREEN + (15 * 40) + 27
            sta SCREEN + (15 * 40) + 28

            lda difficulty
            cmp #DIFF_EASY
            beq draw_diff_easy
            cmp #DIFF_NORMAL
            beq draw_diff_normal
            jmp draw_diff_hard

draw_diff_easy:
            ldx #0
draw_easy_text:
            lda easy_text,x
            beq draw_diff_done
            sta SCREEN + (15 * 40) + 24,x
            lda #EASY_COL
            sta COLRAM + (15 * 40) + 24,x
            inx
            jmp draw_easy_text

draw_diff_normal:
            ldx #0
draw_normal_text:
            lda normal_text,x
            beq draw_diff_done
            sta SCREEN + (15 * 40) + 24,x
            lda #NORMAL_COL
            sta COLRAM + (15 * 40) + 24,x
            inx
            jmp draw_normal_text

draw_diff_hard:
            ldx #0
draw_hard_text:
            lda hard_text,x
            beq draw_diff_done
            sta SCREEN + (15 * 40) + 24,x
            lda #HARD_COL
            sta COLRAM + (15 * 40) + 24,x
            inx
            jmp draw_hard_text

draw_diff_done:
            rts

easy_text:
            !scr "easy"
            !byte 0

normal_text:
            !scr "normal"
            !byte 0

hard_text:
            !scr "hard"
            !byte 0

; ----------------------------------------------------------------------------
; Draw Practice Mode Section
; ----------------------------------------------------------------------------

draw_practice_mode:
            ; Draw "PRACTICE:" label
            ldx #0
draw_prac_label:
            lda prac_label,x
            beq draw_prac_label_done
            sta SCREEN + (17 * 40) + 12,x
            lda #TITLE_COL
            sta COLRAM + (17 * 40) + 12,x
            inx
            jmp draw_prac_label
draw_prac_label_done:

            ; Draw current state
            jsr draw_practice_state

            ; Draw speed section
            ldx #0
draw_speed_label:
            lda speed_label,x
            beq draw_speed_label_done
            sta SCREEN + (18 * 40) + 14,x
            lda #TITLE_COL
            sta COLRAM + (18 * 40) + 14,x
            inx
            jmp draw_speed_label
draw_speed_label_done:

            jsr draw_speed_state
            rts

prac_label:
            !scr "practice:"
            !byte 0

speed_label:
            !scr "speed:"
            !byte 0

; Draw ON/OFF based on practice_mode
draw_practice_state:
            lda practice_mode
            beq draw_prac_off
            ; Draw ON
            lda #'o'
            sta SCREEN + (17 * 40) + 22
            lda #'n'
            sta SCREEN + (17 * 40) + 23
            lda #CHAR_SPACE
            sta SCREEN + (17 * 40) + 24
            lda #PRACTICE_COL
            sta COLRAM + (17 * 40) + 22
            sta COLRAM + (17 * 40) + 23
            rts

draw_prac_off:
            ; Draw OFF
            lda #'o'
            sta SCREEN + (17 * 40) + 22
            lda #'f'
            sta SCREEN + (17 * 40) + 23
            lda #'f'
            sta SCREEN + (17 * 40) + 24
            lda #SUBTITLE_COL
            sta COLRAM + (17 * 40) + 22
            sta COLRAM + (17 * 40) + 23
            sta COLRAM + (17 * 40) + 24
            rts

; Draw speed (0.5x / 0.75x / 1.0x)
draw_speed_state:
            ; Clear speed area
            lda #CHAR_SPACE
            sta SCREEN + (18 * 40) + 21
            sta SCREEN + (18 * 40) + 22
            sta SCREEN + (18 * 40) + 23
            sta SCREEN + (18 * 40) + 24
            sta SCREEN + (18 * 40) + 25

            lda speed_setting
            beq draw_speed_half
            cmp #1
            beq draw_speed_3qrtr
            jmp draw_speed_normal

draw_speed_half:
            ldx #0
draw_half_text:
            lda half_text,x
            beq draw_speed_done
            sta SCREEN + (18 * 40) + 21,x
            lda #EASY_COL           ; Green - slowest
            sta COLRAM + (18 * 40) + 21,x
            inx
            jmp draw_half_text

draw_speed_3qrtr:
            ldx #0
draw_3qrtr_text:
            lda qrtr_text,x
            beq draw_speed_done
            sta SCREEN + (18 * 40) + 21,x
            lda #NORMAL_COL         ; Yellow - medium
            sta COLRAM + (18 * 40) + 21,x
            inx
            jmp draw_3qrtr_text

draw_speed_normal:
            ldx #0
draw_normal_speed_text:
            lda full_text,x
            beq draw_speed_done
            sta SCREEN + (18 * 40) + 21,x
            lda #TITLE_COL          ; White - full speed
            sta COLRAM + (18 * 40) + 21,x
            inx
            jmp draw_normal_speed_text

draw_speed_done:
            rts

half_text:
            !scr "0.5x"
            !byte 0

qrtr_text:
            !scr "0.75x"
            !byte 0

full_text:
            !scr "1.0x"
            !byte 0

; ----------------------------------------------------------------------------
; Draw Menu Cursor
; ----------------------------------------------------------------------------

draw_cursor:
            ; Clear all cursor positions
            lda #CHAR_SPACE
            sta SCREEN + (8 * 40) + 12
            sta SCREEN + (10 * 40) + 12
            sta SCREEN + (12 * 40) + 12
            sta SCREEN + (14 * 40) + 12

            ; Draw cursor at current position
            lda cursor_pos
            beq cursor_song1
            cmp #1
            beq cursor_song2
            cmp #2
            beq cursor_song3
            jmp cursor_song4

cursor_song1:
            lda #CHAR_CURSOR
            sta SCREEN + (8 * 40) + 12
            lda #CURSOR_COL
            sta COLRAM + (8 * 40) + 12
            rts

cursor_song2:
            lda #CHAR_CURSOR
            sta SCREEN + (10 * 40) + 12
            lda #CURSOR_COL
            sta COLRAM + (10 * 40) + 12
            rts

cursor_song3:
            lda #CHAR_CURSOR
            sta SCREEN + (12 * 40) + 12
            lda #CURSOR_COL
            sta COLRAM + (12 * 40) + 12
            rts

cursor_song4:
            lda #CHAR_CURSOR
            sta SCREEN + (14 * 40) + 12
            lda #CURSOR_COL
            sta COLRAM + (14 * 40) + 12
            rts

; ----------------------------------------------------------------------------
; Update Menu State
; ----------------------------------------------------------------------------

update_menu:
            ; Handle key delay
            lda key_delay_count
            beq menu_check_input
            dec key_delay_count
            jmp menu_check_fire

menu_check_input:
            ; Check joystick up
            lda CIA1_PRA
            and #$01            ; Bit 0 = up
            beq menu_up_pressed

            ; Check joystick down
            lda CIA1_PRA
            and #$02            ; Bit 1 = down
            beq menu_down_pressed

            ; Check joystick left (difficulty)
            lda CIA1_PRA
            and #$04            ; Bit 2 = left
            beq menu_left_pressed

            ; Check joystick right (difficulty)
            lda CIA1_PRA
            and #$08            ; Bit 3 = right
            beq menu_right_pressed

            jmp menu_check_fire

menu_up_pressed:
            lda cursor_pos
            beq menu_set_delay  ; Already at top
            dec cursor_pos
            jsr play_menu_move
            jsr draw_cursor
            jmp menu_set_delay

menu_down_pressed:
            lda cursor_pos
            cmp #NUM_SONGS-1
            bcs menu_set_delay  ; Already at bottom
            inc cursor_pos
            jsr play_menu_move
            jsr draw_cursor
            jmp menu_set_delay

menu_left_pressed:
            lda difficulty
            beq menu_set_delay  ; Already at Easy
            dec difficulty
            jsr play_menu_move
            jsr draw_current_difficulty
            jmp menu_set_delay

menu_right_pressed:
            lda difficulty
            cmp #DIFF_HARD
            bcs menu_set_delay  ; Already at Hard
            inc difficulty
            jsr play_menu_move
            jsr draw_current_difficulty
            jmp menu_set_delay

menu_set_delay:
            lda #KEY_DELAY
            sta key_delay_count

menu_check_keys:
            ; Check P key for practice toggle (row 1, column 5)
            lda #$FD                ; Row 1
            sta CIA1_PRA
            lda CIA1_PRB
            and #$20                ; Column 5 = P
            beq menu_p_pressed

            ; Check + key (row 0, column 0 = plus on keyboard)
            lda #$FE                ; Row 0
            sta CIA1_PRA
            lda CIA1_PRB
            and #$01                ; Column 0 = +
            beq menu_plus_pressed

            ; Check - key (row 5, column 3)
            lda #$DF                ; Row 5
            sta CIA1_PRA
            lda CIA1_PRB
            and #$08                ; Column 3 = -
            beq menu_minus_pressed

            jmp menu_check_fire

menu_p_pressed:
            ; Toggle practice mode
            lda practice_mode
            eor #1
            sta practice_mode
            jsr play_menu_move
            jsr draw_practice_state
            lda #KEY_DELAY
            sta key_delay_count
            jmp menu_check_fire

menu_plus_pressed:
            ; Increase speed (towards 1.0x)
            lda speed_setting
            cmp #NUM_SPEEDS-1
            bcs menu_check_fire     ; Already at max
            inc speed_setting
            jsr play_menu_move
            jsr draw_speed_state
            lda #KEY_DELAY
            sta key_delay_count
            jmp menu_check_fire

menu_minus_pressed:
            ; Decrease speed (towards 0.5x)
            lda speed_setting
            beq menu_check_fire     ; Already at min
            dec speed_setting
            jsr play_menu_move
            jsr draw_speed_state
            lda #KEY_DELAY
            sta key_delay_count

menu_check_fire:
            ; Check for fire button
            lda CIA1_PRA
            and #$10
            beq menu_fire_pressed

            ; Check space bar
            lda #$7F
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10
            beq menu_fire_pressed

            lda #$FF
            sta CIA1_PRA
            rts

menu_fire_pressed:
            lda #$FF
            sta CIA1_PRA

            ; Play select sound
            jsr play_menu_select

            ; Store selected song
            lda cursor_pos
            sta selected_song

            ; Set difficulty parameters
            jsr set_difficulty_params

            ; Transition to game
            jsr transition_to_game
            rts

; ----------------------------------------------------------------------------
; Set Difficulty Parameters
; ----------------------------------------------------------------------------

set_difficulty_params:
            lda difficulty
            cmp #DIFF_EASY
            beq set_diff_easy
            cmp #DIFF_NORMAL
            beq set_diff_normal
            jmp set_diff_hard

set_diff_easy:
            lda #PERFECT_WINDOW_EASY
            sta perfect_window
            lda #GOOD_WINDOW_EASY
            sta good_window
            lda #HEALTH_MISS_EASY
            sta health_miss_amt
            rts

set_diff_normal:
            lda #PERFECT_WINDOW_NORMAL
            sta perfect_window
            lda #GOOD_WINDOW_NORMAL
            sta good_window
            lda #HEALTH_MISS_NORMAL
            sta health_miss_amt
            rts

set_diff_hard:
            lda #PERFECT_WINDOW_HARD
            sta perfect_window
            lda #GOOD_WINDOW_HARD
            sta good_window
            lda #HEALTH_MISS_HARD
            sta health_miss_amt
            rts

; ----------------------------------------------------------------------------
; Transition to Game
; ----------------------------------------------------------------------------

transition_to_game:
            ; Set up tempo based on song selection
            lda selected_song
            beq setup_song1
            cmp #1
            beq setup_song2
            cmp #2
            beq setup_song3
            jmp setup_song4

setup_song1:
            lda #TEMPO_SONG1
            sta frames_per_beat
            lda #LENGTH_SONG1
            sta song_length

            ; Select difficulty variant for Song 1
            lda difficulty
            cmp #DIFF_EASY
            beq load_s1_easy
            cmp #DIFF_NORMAL
            beq load_s1_normal
            jmp load_s1_hard

load_s1_easy:
            lda #<song1_easy
            sta song_data_ptr
            lda #>song1_easy
            sta song_data_ptr+1
            jmp start_game

load_s1_normal:
            lda #<song1_normal
            sta song_data_ptr
            lda #>song1_normal
            sta song_data_ptr+1
            jmp start_game

load_s1_hard:
            lda #<song1_hard
            sta song_data_ptr
            lda #>song1_hard
            sta song_data_ptr+1
            jmp start_game

setup_song2:
            lda #TEMPO_SONG2
            sta frames_per_beat
            lda #LENGTH_SONG2
            sta song_length

            ; Select difficulty variant for Song 2
            lda difficulty
            cmp #DIFF_EASY
            beq load_s2_easy
            cmp #DIFF_NORMAL
            beq load_s2_normal
            jmp load_s2_hard

load_s2_easy:
            lda #<song2_easy
            sta song_data_ptr
            lda #>song2_easy
            sta song_data_ptr+1
            jmp start_game

load_s2_normal:
            lda #<song2_normal
            sta song_data_ptr
            lda #>song2_normal
            sta song_data_ptr+1
            jmp start_game

load_s2_hard:
            lda #<song2_hard
            sta song_data_ptr
            lda #>song2_hard
            sta song_data_ptr+1
            jmp start_game

setup_song3:
            lda #TEMPO_SONG3
            sta frames_per_beat
            lda #LENGTH_SONG3
            sta song_length

            ; Select difficulty variant for Song 3
            lda difficulty
            cmp #DIFF_EASY
            beq load_s3_easy
            cmp #DIFF_NORMAL
            beq load_s3_normal
            jmp load_s3_hard

load_s3_easy:
            lda #<song3_easy
            sta song_data_ptr
            lda #>song3_easy
            sta song_data_ptr+1
            jmp start_game

load_s3_normal:
            lda #<song3_normal
            sta song_data_ptr
            lda #>song3_normal
            sta song_data_ptr+1
            jmp start_game

load_s3_hard:
            lda #<song3_hard
            sta song_data_ptr
            lda #>song3_hard
            sta song_data_ptr+1
            jmp start_game

setup_song4:
            lda #TEMPO_SONG4
            sta frames_per_beat
            lda #LENGTH_SONG4
            sta song_length

            ; Select difficulty variant for Song 4
            lda difficulty
            cmp #DIFF_EASY
            beq load_s4_easy
            cmp #DIFF_NORMAL
            beq load_s4_normal
            jmp load_s4_hard

load_s4_easy:
            lda #<song4_easy
            sta song_data_ptr
            lda #>song4_easy
            sta song_data_ptr+1
            jmp start_game

load_s4_normal:
            lda #<song4_normal
            sta song_data_ptr
            lda #>song4_normal
            sta song_data_ptr+1
            jmp start_game

load_s4_hard:
            lda #<song4_hard
            sta song_data_ptr
            lda #>song4_hard
            sta song_data_ptr+1

start_game:
            ; Apply speed modifier to tempo
            jsr apply_speed_modifier

            ; Initialise game
            jsr init_game
            lda #STATE_PLAYING
            sta game_state
            rts

; Apply speed modifier to frames_per_beat
apply_speed_modifier:
            lda speed_setting
            beq speed_half_tempo    ; 0 = 0.5x
            cmp #1
            beq speed_3qrtr_tempo   ; 1 = 0.75x
            rts                     ; 2 = 1.0x, no change

speed_half_tempo:
            ; 0.5x speed = double frames_per_beat
            asl frames_per_beat
            rts

speed_3qrtr_tempo:
            ; 0.75x speed = frames_per_beat + frames_per_beat/3
            ; Approximation: add half (will be roughly 1.5x, close to 0.75x)
            lda frames_per_beat
            lsr                     ; Divide by 2
            clc
            adc frames_per_beat     ; Add to original = 1.5x frames
            sta frames_per_beat
            rts

; Song data pointers
song_data_ptr:
            !word 0

; ----------------------------------------------------------------------------
; Play Menu Move Sound
; ----------------------------------------------------------------------------

play_menu_move:
            lda #0
            sta SID_V3_FREQ_LO
            lda #MENU_MOVE_FREQ
            sta SID_V3_FREQ_HI
            lda #$08
            sta SID_V3_PWHI
            lda #MENU_MOVE_AD
            sta SID_V3_AD
            lda #MENU_MOVE_SR
            sta SID_V3_SR
            lda #MENU_MOVE_WAVE
            ora #$01            ; Gate on
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Play Menu Select Sound
; ----------------------------------------------------------------------------

play_menu_select:
            lda #0
            sta SID_V3_FREQ_LO
            lda #MENU_SELECT_FREQ
            sta SID_V3_FREQ_HI
            lda #$08
            sta SID_V3_PWHI
            lda #MENU_SELECT_AD
            sta SID_V3_AD
            lda #MENU_SELECT_SR
            sta SID_V3_SR
            lda #MENU_SELECT_WAVE
            ora #$01            ; Gate on
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Initialize Game
; ----------------------------------------------------------------------------

init_game:
            jsr init_screen
            jsr init_notes
            jsr init_score
            jsr init_health
            jsr init_combo
            jsr init_song

            rts

; ----------------------------------------------------------------------------
; Initialize Combo
; ----------------------------------------------------------------------------

init_combo:
            lda #0
            sta combo
            sta max_combo
            jsr display_combo
            rts

; ----------------------------------------------------------------------------
; Update Playing State
; ----------------------------------------------------------------------------

update_playing:
            inc frame_count
            lda frame_count
            cmp frames_per_beat
            bcc no_new_beat

            lda #0
            sta frame_count
            jsr advance_song
            jsr check_spawn_note

no_new_beat:
            jsr update_notes
            jsr reset_track_colours
            jsr update_border_flash
            jsr check_keys
            jsr check_song_end

            rts

; ----------------------------------------------------------------------------
; Update Results State
; ----------------------------------------------------------------------------

update_results:
            ; Check for fire to return to menu
            lda CIA1_PRA
            and #$10
            beq results_fire

            ; Also check space bar
            lda #$7F
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10
            beq results_fire

            lda #$FF
            sta CIA1_PRA
            rts

results_fire:
            lda #$FF
            sta CIA1_PRA

            jsr play_menu_select

            ; Return to menu
            jsr show_menu
            lda #STATE_MENU
            sta game_state
            rts

; ----------------------------------------------------------------------------
; Update Game Over State
; ----------------------------------------------------------------------------

update_gameover:
            ; Check for fire to return to menu
            lda CIA1_PRA
            and #$10
            beq gameover_fire

            ; Also check space bar
            lda #$7F
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10
            beq gameover_fire

            lda #$FF
            sta CIA1_PRA
            rts

gameover_fire:
            lda #$FF
            sta CIA1_PRA

            jsr play_menu_select

            ; Return to menu
            jsr show_menu
            lda #STATE_MENU
            sta game_state
            rts

; ----------------------------------------------------------------------------
; Initialize Screen (Gameplay)
; ----------------------------------------------------------------------------

init_screen:
            ; Enable custom charset
            lda #$1C            ; Character ROM at $3000
            sta CHARPTR

            ; Set colours
            lda #BORDER_COL
            sta BORDER
            lda #BG_COL
            sta BGCOL

            ; Clear screen
            ldx #0
            lda #CHAR_SPACE
clear_screen:
            sta SCREEN,x
            sta SCREEN+$100,x
            sta SCREEN+$200,x
            sta SCREEN+$2E8,x
            inx
            bne clear_screen

            ; Draw tracks
            ldx #0
draw_tracks:
            lda #CHAR_TRACK
            sta SCREEN + (TRACK1_ROW * 40),x
            sta SCREEN + (TRACK2_ROW * 40),x
            sta SCREEN + (TRACK3_ROW * 40),x
            lda #TRACK_LINE_COL
            sta COLRAM + (TRACK1_ROW * 40),x
            sta COLRAM + (TRACK2_ROW * 40),x
            sta COLRAM + (TRACK3_ROW * 40),x
            inx
            cpx #38
            bne draw_tracks

            ; Draw hit zones
            lda #CHAR_HITZONE
            sta SCREEN + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
            sta SCREEN + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
            sta SCREEN + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN
            lda #HIT_ZONE_COL
            sta COLRAM + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
            sta COLRAM + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
            sta COLRAM + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN

            ; Draw track labels
            lda #$31            ; "1"
            sta SCREEN + (TRACK1_ROW * 40)
            lda #$32            ; "2"
            sta SCREEN + (TRACK2_ROW * 40)
            lda #$33            ; "3"
            sta SCREEN + (TRACK3_ROW * 40)
            lda #1
            sta COLRAM + (TRACK1_ROW * 40)
            sta COLRAM + (TRACK2_ROW * 40)
            sta COLRAM + (TRACK3_ROW * 40)

            ; Draw HUD labels
            ldx #0
draw_score_label:
            lda score_label,x
            beq draw_miss_label_start
            sta SCREEN,x
            lda #7
            sta COLRAM,x
            inx
            jmp draw_score_label

draw_miss_label_start:
            ldx #0
draw_miss_label:
            lda miss_label,x
            beq draw_combo_label_start
            sta SCREEN + 14,x
            lda #2
            sta COLRAM + 14,x
            inx
            jmp draw_miss_label

draw_combo_label_start:
            ldx #0
draw_combo_label:
            lda combo_label,x
            beq draw_health_label_start
            sta SCREEN + (COMBO_ROW * 40) + 27,x
            lda #COMBO_COL
            sta COLRAM + (COMBO_ROW * 40) + 27,x
            inx
            jmp draw_combo_label

draw_health_label_start:
            ldx #0
draw_health_label:
            lda health_label,x
            beq draw_progress_label_start
            sta SCREEN + (HEALTH_ROW * 40),x
            lda #HEALTH_COL
            sta COLRAM + (HEALTH_ROW * 40),x
            inx
            jmp draw_health_label

draw_progress_label_start:
            ldx #0
draw_progress_label:
            lda progress_label,x
            beq labels_done
            sta SCREEN + (PROGRESS_ROW * 40),x
            lda #PROGRESS_COL
            sta COLRAM + (PROGRESS_ROW * 40),x
            inx
            jmp draw_progress_label

labels_done:
            ; Draw song name based on selection
            lda selected_song
            beq draw_name_song1
            jmp draw_name_song2

draw_name_song1:
            ldx #0
draw_sn1:
            lda song1_name,x
            beq draw_difficulty_hud
            sta SCREEN + 28,x
            lda #11
            sta COLRAM + 28,x
            inx
            jmp draw_sn1

draw_name_song2:
            ldx #0
draw_sn2:
            lda song2_name,x
            beq draw_difficulty_hud
            sta SCREEN + 26,x
            lda #11
            sta COLRAM + 26,x
            inx
            jmp draw_sn2

draw_difficulty_hud:
            ; Show difficulty on gameplay HUD
            lda difficulty
            cmp #DIFF_EASY
            beq draw_hud_easy
            cmp #DIFF_NORMAL
            beq draw_hud_normal
            jmp draw_hud_hard

draw_hud_easy:
            ldx #0
draw_hud_e:
            lda easy_text,x
            beq draw_song_name_done
            sta SCREEN + (COMBO_ROW * 40),x
            lda #EASY_COL
            sta COLRAM + (COMBO_ROW * 40),x
            inx
            jmp draw_hud_e

draw_hud_normal:
            ldx #0
draw_hud_n:
            lda normal_text,x
            beq draw_song_name_done
            sta SCREEN + (COMBO_ROW * 40),x
            lda #NORMAL_COL
            sta COLRAM + (COMBO_ROW * 40),x
            inx
            jmp draw_hud_n

draw_hud_hard:
            ldx #0
draw_hud_h:
            lda hard_text,x
            beq draw_song_name_done
            sta SCREEN + (COMBO_ROW * 40),x
            lda #HARD_COL
            sta COLRAM + (COMBO_ROW * 40),x
            inx
            jmp draw_hud_h

draw_song_name_done:
            rts

score_label:
            !scr "score:"
            !byte 0
miss_label:
            !scr "miss:"
            !byte 0
combo_label:
            !scr "combo:"
            !byte 0
health_label:
            !scr "health:"
            !byte 0
progress_label:
            !scr "song:"
            !byte 0

; ----------------------------------------------------------------------------
; Initialize Notes
; ----------------------------------------------------------------------------

init_notes:
            ldx #0
            lda #0
clear_notes:
            sta note_track,x
            sta note_col,x
            sta note_freq,x
            inx
            cpx #MAX_NOTES
            bne clear_notes
            rts

; ----------------------------------------------------------------------------
; Initialize Score
; ----------------------------------------------------------------------------

init_score:
            lda #0
            sta score_lo
            sta score_hi
            sta miss_count
            sta perfect_count
            sta good_count
            jsr display_score
            jsr display_misses
            rts

; ----------------------------------------------------------------------------
; Initialize Health
; ----------------------------------------------------------------------------

init_health:
            lda #HEALTH_START
            sta health
            jsr display_health
            rts

; ----------------------------------------------------------------------------
; Initialize Song
; ----------------------------------------------------------------------------

init_song:
            lda #0
            sta frame_count
            sta beat_count
            sta song_beat
            sta song_ended

            ; Point to selected song data
            lda song_data_ptr
            sta song_pos
            lda song_data_ptr+1
            sta song_pos_hi

            jsr display_progress
            rts

; ----------------------------------------------------------------------------
; Initialize SID
; ----------------------------------------------------------------------------

init_sid:
            ; Clear SID
            ldx #$18
            lda #0
clear_sid:
            sta SID,x
            dex
            bpl clear_sid

            ; Set volume
            lda #$0F
            sta SID_VOLUME

            ; Set pulse widths
            lda #PULSE_WIDTH
            sta SID_V1_PWHI
            sta SID_V2_PWHI
            sta SID_V3_PWHI

            ; Set ADSR for all voices
            lda #VOICE_AD
            sta SID_V1_AD
            sta SID_V2_AD
            sta SID_V3_AD

            lda #VOICE_SR
            sta SID_V1_SR
            sta SID_V2_SR
            sta SID_V3_SR

            rts

; ----------------------------------------------------------------------------
; Copy Custom Charset
; ----------------------------------------------------------------------------

copy_charset:
            ; Copy default ROM charset to RAM first
            sei
            lda #$33
            sta $01

            ldx #0
copy_rom_chars:
            lda $D000,x
            sta CHARSET,x
            lda $D100,x
            sta CHARSET+$100,x
            lda $D200,x
            sta CHARSET+$200,x
            lda $D300,x
            sta CHARSET+$300,x
            lda $D400,x
            sta CHARSET+$400,x
            lda $D500,x
            sta CHARSET+$500,x
            lda $D600,x
            sta CHARSET+$600,x
            lda $D700,x
            sta CHARSET+$700,x
            inx
            bne copy_rom_chars

            lda #$37
            sta $01
            cli

            ; Now add custom characters

            ; Character 128 - Note (solid circle)
            lda #%00111100
            sta CHARSET + (128 * 8) + 0
            lda #%01111110
            sta CHARSET + (128 * 8) + 1
            lda #%11111111
            sta CHARSET + (128 * 8) + 2
            lda #%11111111
            sta CHARSET + (128 * 8) + 3
            lda #%11111111
            sta CHARSET + (128 * 8) + 4
            lda #%11111111
            sta CHARSET + (128 * 8) + 5
            lda #%01111110
            sta CHARSET + (128 * 8) + 6
            lda #%00111100
            sta CHARSET + (128 * 8) + 7

            ; Character 129 - Track line (dashes)
            lda #%00000000
            sta CHARSET + (129 * 8) + 0
            lda #%00000000
            sta CHARSET + (129 * 8) + 1
            lda #%00000000
            sta CHARSET + (129 * 8) + 2
            lda #%11001100
            sta CHARSET + (129 * 8) + 3
            lda #%11001100
            sta CHARSET + (129 * 8) + 4
            lda #%00000000
            sta CHARSET + (129 * 8) + 5
            lda #%00000000
            sta CHARSET + (129 * 8) + 6
            lda #%00000000
            sta CHARSET + (129 * 8) + 7

            ; Character 130 - Hit zone (vertical bars)
            lda #%10000001
            sta CHARSET + (130 * 8) + 0
            lda #%10000001
            sta CHARSET + (130 * 8) + 1
            lda #%10000001
            sta CHARSET + (130 * 8) + 2
            lda #%10000001
            sta CHARSET + (130 * 8) + 3
            lda #%10000001
            sta CHARSET + (130 * 8) + 4
            lda #%10000001
            sta CHARSET + (130 * 8) + 5
            lda #%10000001
            sta CHARSET + (130 * 8) + 6
            lda #%10000001
            sta CHARSET + (130 * 8) + 7

            ; Character 131 - Bar full (solid block)
            lda #%11111111
            sta CHARSET + (131 * 8) + 0
            sta CHARSET + (131 * 8) + 1
            sta CHARSET + (131 * 8) + 2
            sta CHARSET + (131 * 8) + 3
            sta CHARSET + (131 * 8) + 4
            sta CHARSET + (131 * 8) + 5
            sta CHARSET + (131 * 8) + 6
            sta CHARSET + (131 * 8) + 7

            ; Character 132 - Bar empty (hollow block)
            lda #%11111111
            sta CHARSET + (132 * 8) + 0
            lda #%10000001
            sta CHARSET + (132 * 8) + 1
            sta CHARSET + (132 * 8) + 2
            sta CHARSET + (132 * 8) + 3
            sta CHARSET + (132 * 8) + 4
            sta CHARSET + (132 * 8) + 5
            sta CHARSET + (132 * 8) + 6
            lda #%11111111
            sta CHARSET + (132 * 8) + 7

            rts

; ----------------------------------------------------------------------------
; Advance Song
; ----------------------------------------------------------------------------

advance_song:
            inc song_beat
            jsr display_progress
            rts

; ----------------------------------------------------------------------------
; Check Spawn Note
; ----------------------------------------------------------------------------

check_spawn_note:
            ; Check if song has ended
            lda song_ended
            bne spawn_done

            ; Get pointer to current position in song
            lda song_pos
            sta ZP_PTR
            lda song_pos_hi
            sta ZP_PTR_HI

            ; Read beat number
            ldy #0
            lda (ZP_PTR),y

            ; Check for end marker
            cmp #$FF
            beq song_end_marker

            ; Check if this beat matches
            cmp song_beat
            bne spawn_done

            ; Spawn this note
            iny
            lda (ZP_PTR),y      ; Track
            sta temp_track
            iny
            lda (ZP_PTR),y      ; Frequency

            ; Find free note slot
            ldx #0
find_slot:
            lda note_track,x
            beq found_slot
            inx
            cpx #MAX_NOTES
            bne find_slot
            jmp advance_song_ptr  ; No free slot, skip note

found_slot:
            lda temp_track
            sta note_track,x
            lda #NOTE_SPAWN_COL
            sta note_col,x
            ldy #2
            lda (ZP_PTR),y
            sta note_freq,x
            jsr draw_note

advance_song_ptr:
            ; Move to next note in song
            lda song_pos
            clc
            adc #3
            sta song_pos
            lda song_pos_hi
            adc #0
            sta song_pos_hi

            ; Check if there are more notes on this beat
            jmp check_spawn_note

song_end_marker:
            lda #1
            sta song_ended
spawn_done:
            rts

; ----------------------------------------------------------------------------
; Update Notes
; ----------------------------------------------------------------------------

update_notes:
            ldx #0
update_notes_loop:
            lda note_track,x
            beq update_next_note

            ; Erase at old position
            jsr erase_note

            ; Move note left
            dec note_col,x

            ; Check if past hit zone (missed)
            lda note_col,x
            cmp #HIT_ZONE_START
            bcs note_still_active

            ; Note was missed
            lda note_track,x
            sta miss_track
            lda #0
            sta note_track,x
            jsr handle_miss
            jmp update_next_note

note_still_active:
            jsr draw_note

update_next_note:
            inx
            cpx #MAX_NOTES
            bne update_notes_loop
            rts

; ----------------------------------------------------------------------------
; Draw Note
; ----------------------------------------------------------------------------

draw_note:
            lda note_track,x
            cmp #1
            beq draw_note_t1
            cmp #2
            beq draw_note_t2
            jmp draw_note_t3

draw_note_t1:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK1_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK1_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_NOTE
            ldy #0
            sta (ZP_PTR),y

            ; Set colour
            lda note_col,x
            clc
            adc #<(COLRAM + TRACK1_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK1_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK1_NOTE_COL
            sta (ZP_PTR),y
            rts

draw_note_t2:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK2_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK2_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_NOTE
            ldy #0
            sta (ZP_PTR),y

            lda note_col,x
            clc
            adc #<(COLRAM + TRACK2_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK2_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK2_NOTE_COL
            sta (ZP_PTR),y
            rts

draw_note_t3:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK3_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK3_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_NOTE
            ldy #0
            sta (ZP_PTR),y

            lda note_col,x
            clc
            adc #<(COLRAM + TRACK3_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK3_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK3_NOTE_COL
            sta (ZP_PTR),y
            rts

; ----------------------------------------------------------------------------
; Erase Note
; ----------------------------------------------------------------------------

erase_note:
            lda note_track,x
            cmp #1
            beq erase_note_t1
            cmp #2
            beq erase_note_t2
            jmp erase_note_t3

erase_note_t1:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK1_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK1_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_TRACK
            ldy #0
            sta (ZP_PTR),y

            lda note_col,x
            clc
            adc #<(COLRAM + TRACK1_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK1_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK_LINE_COL
            sta (ZP_PTR),y
            rts

erase_note_t2:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK2_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK2_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_TRACK
            ldy #0
            sta (ZP_PTR),y

            lda note_col,x
            clc
            adc #<(COLRAM + TRACK2_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK2_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK_LINE_COL
            sta (ZP_PTR),y
            rts

erase_note_t3:
            lda note_col,x
            clc
            adc #<(SCREEN + TRACK3_ROW * 40)
            sta ZP_PTR
            lda #>(SCREEN + TRACK3_ROW * 40)
            adc #0
            sta ZP_PTR_HI

            lda #CHAR_TRACK
            ldy #0
            sta (ZP_PTR),y

            lda note_col,x
            clc
            adc #<(COLRAM + TRACK3_ROW * 40)
            sta ZP_PTR
            lda #>(COLRAM + TRACK3_ROW * 40)
            adc #0
            sta ZP_PTR_HI
            lda #TRACK_LINE_COL
            sta (ZP_PTR),y
            rts

; ----------------------------------------------------------------------------
; Handle Miss
; ----------------------------------------------------------------------------

handle_miss:
            jsr play_miss_sound
            jsr break_combo

            ; In practice mode, don't decrease health
            lda practice_mode
            bne skip_health_loss

            ; Decrease health (using difficulty-adjusted amount)
            lda health_miss_amt
            jsr decrease_health

skip_health_loss:
            ; Flash border red
            lda #MISS_COL
            sta BORDER
            lda #8
            sta border_flash

            ; Flash the track where miss happened
            lda miss_track
            cmp #1
            beq flash_miss_t1
            cmp #2
            beq flash_miss_t2
            jmp flash_miss_t3

flash_miss_t1:
            ldx #0
            lda #MISS_COL
flash_m1_loop:
            sta COLRAM + (TRACK1_ROW * 40),x
            inx
            cpx #38
            bne flash_m1_loop
            rts

flash_miss_t2:
            ldx #0
            lda #MISS_COL
flash_m2_loop:
            sta COLRAM + (TRACK2_ROW * 40),x
            inx
            cpx #38
            bne flash_m2_loop
            rts

flash_miss_t3:
            ldx #0
            lda #MISS_COL
flash_m3_loop:
            sta COLRAM + (TRACK3_ROW * 40),x
            inx
            cpx #38
            bne flash_m3_loop
            rts

; ----------------------------------------------------------------------------
; Play Miss Sound
; ----------------------------------------------------------------------------

play_miss_sound:
            inc miss_count
            jsr display_misses

            lda #0
            sta SID_V3_FREQ_LO
            lda #MISS_FREQ
            sta SID_V3_FREQ_HI
            lda #MISS_AD
            sta SID_V3_AD
            lda #MISS_SR
            sta SID_V3_SR
            lda #MISS_WAVE
            ora #$01
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Play Perfect Sound
; ----------------------------------------------------------------------------

play_perfect_sound:
            lda #0
            sta SID_V3_FREQ_LO
            lda #PERFECT_SFX_FREQ
            sta SID_V3_FREQ_HI
            lda #PERFECT_SFX_AD
            sta SID_V3_AD
            lda #PERFECT_SFX_SR
            sta SID_V3_SR
            lda #PERFECT_SFX_WAVE
            ora #$01
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Play Good Sound
; ----------------------------------------------------------------------------

play_good_sound:
            lda #0
            sta SID_V3_FREQ_LO
            lda #GOOD_SFX_FREQ
            sta SID_V3_FREQ_HI
            lda #GOOD_SFX_AD
            sta SID_V3_AD
            lda #GOOD_SFX_SR
            sta SID_V3_SR
            lda #GOOD_SFX_WAVE
            ora #$01
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Increase Health
; ----------------------------------------------------------------------------

increase_health:
            clc
            adc health
            cmp #HEALTH_MAX
            bcc health_ok
            lda #HEALTH_MAX
health_ok:
            sta health
            jsr display_health
            rts

; ----------------------------------------------------------------------------
; Decrease Health
; ----------------------------------------------------------------------------

decrease_health:
            sta temp_track
            lda health
            sec
            sbc temp_track
            bcs health_not_zero
            lda #0
health_not_zero:
            sta health
            jsr display_health

            ; Check for game over
            lda health
            bne no_game_over
            jsr show_gameover
            lda #STATE_GAMEOVER
            sta game_state
no_game_over:
            rts

; ----------------------------------------------------------------------------
; Display Health Bar
; ----------------------------------------------------------------------------

display_health:
            ; Calculate filled blocks (health / 4 = blocks, max 16)
            lda health
            lsr
            lsr
            sta temp_track

            ldx #0
draw_health_bar:
            cpx temp_track
            bcs draw_empty_health
            lda #CHAR_BAR_FULL
            jmp store_health_char
draw_empty_health:
            lda #CHAR_BAR_EMPTY
store_health_char:
            sta SCREEN + (HEALTH_ROW * 40) + 8,x
            lda #HEALTH_COL
            sta COLRAM + (HEALTH_ROW * 40) + 8,x
            inx
            cpx #16
            bne draw_health_bar
            rts

; ----------------------------------------------------------------------------
; Display Progress Bar
; ----------------------------------------------------------------------------

display_progress:
            ; Calculate progress (song_beat / 4)
            lda song_beat
            lsr
            lsr
            sta temp_track

            ldx #0
draw_progress_bar:
            cpx temp_track
            bcs draw_empty_progress
            lda #CHAR_BAR_FULL
            jmp store_progress_char
draw_empty_progress:
            lda #CHAR_BAR_EMPTY
store_progress_char:
            sta SCREEN + (PROGRESS_ROW * 40) + 8,x
            lda #PROGRESS_COL
            sta COLRAM + (PROGRESS_ROW * 40) + 8,x
            inx
            cpx #PROGRESS_WIDTH
            bne draw_progress_bar
            rts

; ----------------------------------------------------------------------------
; Combo System
; ----------------------------------------------------------------------------

increment_combo:
            inc combo
            lda combo
            cmp max_combo
            bcc combo_no_max
            sta max_combo
combo_no_max:
            jsr display_combo
            rts

break_combo:
            lda #0
            sta combo
            jsr display_combo
            rts

display_combo:
            ; Display combo count
            lda combo
            ldx #0
combo_div_100:
            cmp #100
            bcc combo_done_100
            sec
            sbc #100
            inx
            jmp combo_div_100
combo_done_100:
            pha
            txa
            ora #$30
            sta SCREEN + (COMBO_ROW * 40) + 34

            pla
            ldx #0
combo_div_10:
            cmp #10
            bcc combo_done_10
            sec
            sbc #10
            inx
            jmp combo_div_10
combo_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + (COMBO_ROW * 40) + 35

            pla
            ora #$30
            sta SCREEN + (COMBO_ROW * 40) + 36

            ; Colour based on multiplier
            jsr get_multiplier
            cmp #1
            beq combo_col_1x
            cmp #2
            beq combo_col_2x
            cmp #3
            beq combo_col_3x
            jmp combo_col_4x

combo_col_1x:
            lda #11             ; Grey
            ldx #COMBO_BORDER_1 ; Dark grey border
            jmp set_combo_col
combo_col_2x:
            lda #7              ; Yellow
            ldx #COMBO_BORDER_2 ; Green border
            jmp set_combo_col
combo_col_3x:
            lda #5              ; Green
            ldx #COMBO_BORDER_3 ; Yellow border
            jmp set_combo_col
combo_col_4x:
            lda #1              ; White
            ldx #COMBO_BORDER_4 ; Red border (fire!)

set_combo_col:
            sta COLRAM + (COMBO_ROW * 40) + 34
            sta COLRAM + (COMBO_ROW * 40) + 35
            sta COLRAM + (COMBO_ROW * 40) + 36

            ; Update border colour for visual feedback
            lda combo
            beq reset_border    ; No combo = black border
            stx BORDER          ; Set border to tier colour
            rts

reset_border:
            lda #COMBO_BORDER_0
            sta BORDER
            rts

get_multiplier:
            lda combo
            cmp #COMBO_TIER_4
            bcs mult_4x
            cmp #COMBO_TIER_3
            bcs mult_3x
            cmp #COMBO_TIER_2
            bcs mult_2x
            lda #1
            rts
mult_2x:
            lda #2
            rts
mult_3x:
            lda #3
            rts
mult_4x:
            lda #4
            rts

; ----------------------------------------------------------------------------
; Reset Track Colours
; ----------------------------------------------------------------------------

reset_track_colours:
            ldx #1              ; Start at column 1 (skip label)
reset_col_loop:
            lda #TRACK_LINE_COL
            sta COLRAM + (TRACK1_ROW * 40),x
            sta COLRAM + (TRACK2_ROW * 40),x
            sta COLRAM + (TRACK3_ROW * 40),x
            inx
            cpx #38
            bne reset_col_loop

            ; Restore hit zone colours
            lda #HIT_ZONE_COL
            sta COLRAM + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
            sta COLRAM + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
            sta COLRAM + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN

            ; Redraw notes with correct colours
            ldx #0
redraw_loop:
            lda note_track,x
            beq redraw_next
            jsr draw_note
redraw_next:
            inx
            cpx #MAX_NOTES
            bne redraw_loop
            rts

; ----------------------------------------------------------------------------
; Update Border Flash
; ----------------------------------------------------------------------------

update_border_flash:
            lda border_flash
            beq flash_done
            dec border_flash
            bne flash_done
            lda #BORDER_COL
            sta BORDER
flash_done:
            rts

; ----------------------------------------------------------------------------
; Check Keys
; ----------------------------------------------------------------------------

check_keys:
            lda #$FD
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10
            bne check_x_key

            lda #1
            sta key_pressed
            jsr check_hit
            bcc check_x_key
            jsr play_voice1_note
            jsr flash_track1_hit
            jsr award_points

check_x_key:
            lda #$FB
            sta CIA1_PRA
            lda CIA1_PRB
            and #$80
            bne check_c_key

            lda #2
            sta key_pressed
            jsr check_hit
            bcc check_c_key
            jsr play_voice2_note
            jsr flash_track2_hit
            jsr award_points

check_c_key:
            lda #$FB
            sta CIA1_PRA
            lda CIA1_PRB
            and #$10
            bne check_keys_done

            lda #3
            sta key_pressed
            jsr check_hit
            bcc check_keys_done
            jsr play_voice3_note
            jsr flash_track3_hit
            jsr award_points

check_keys_done:
            lda #$FF
            sta CIA1_PRA
            rts

; ----------------------------------------------------------------------------
; Check Hit (with difficulty-adjusted timing windows)
; ----------------------------------------------------------------------------

check_hit:
            ldx #0

check_hit_loop:
            lda note_track,x
            beq check_hit_next

            cmp key_pressed
            bne check_hit_next

            ; Check if note is in hittable range
            lda note_col,x
            cmp #HIT_ZONE_START
            bcc check_hit_next
            cmp #HIT_ZONE_END+1
            bcs check_hit_next

            ; Note is hittable - determine quality based on distance from perfect
            lda note_freq,x
            sta hit_note_freq

            ; Calculate distance from perfect column
            lda note_col,x
            sec
            sbc #PERFECT_COL_POS
            bcs dist_positive
            ; Negative distance - make it positive
            eor #$FF
            clc
            adc #1
dist_positive:
            ; A now contains absolute distance from perfect

            ; Check if within perfect window
            cmp perfect_window
            bcc hit_is_perfect
            beq hit_is_perfect

            ; Check if within good window
            cmp good_window
            bcc hit_is_good
            beq hit_is_good

            ; Outside good window but in hit zone - still counts as good
            jmp hit_is_good

hit_is_perfect:
            lda #2
            sta hit_quality
            jmp hit_found

hit_is_good:
            lda #1
            sta hit_quality

hit_found:
            jsr erase_note
            lda #0
            sta note_track,x
            sec
            rts

check_hit_next:
            inx
            cpx #MAX_NOTES
            bne check_hit_loop

            lda #0
            sta hit_quality
            clc
            rts

; ----------------------------------------------------------------------------
; Check Song End
; ----------------------------------------------------------------------------

check_song_end:
            lda song_ended
            beq not_ended

            ; Check if all notes cleared
            ldx #0
check_notes_clear:
            lda note_track,x
            bne not_ended
            inx
            cpx #MAX_NOTES
            bne check_notes_clear

            ; Add delay before results
            inc end_delay
            lda end_delay
            cmp #END_DELAY_FRAMES
            bcc not_ended

            ; Show results
            jsr show_results
            lda #STATE_RESULTS
            sta game_state

not_ended:
            rts

; ----------------------------------------------------------------------------
; Award Points
; ----------------------------------------------------------------------------

award_points:
            jsr increment_combo

            lda hit_quality
            cmp #2
            beq award_perfect

            ; Good hit
            lda #GOOD_SCORE
            jsr apply_multiplier
            jsr add_score

            inc good_count

            ; Play good sound effect
            jsr play_good_sound

            lda #GOOD_COL
            sta BORDER
            lda #4
            sta border_flash

            lda #HEALTH_GOOD
            jsr increase_health

            jmp award_done

award_perfect:
            ; Perfect hit
            lda #PERFECT_SCORE
            jsr apply_multiplier
            jsr add_score

            inc perfect_count

            ; Play perfect sound effect
            jsr play_perfect_sound

            lda #PERFECT_COL
            sta BORDER
            lda #6
            sta border_flash

            lda #HEALTH_PERFECT
            jsr increase_health

award_done:
            jsr display_score
            rts

; ----------------------------------------------------------------------------
; Apply Multiplier
; ----------------------------------------------------------------------------

apply_multiplier:
            sta base_score
            jsr get_multiplier
            sta current_mult

            lda base_score
            sta score_add_lo
            lda #0
            sta score_add_hi

            lda current_mult
            cmp #1
            beq mult_done_apply

            dec current_mult
mult_add_loop:
            lda score_add_lo
            clc
            adc base_score
            sta score_add_lo
            lda score_add_hi
            adc #0
            sta score_add_hi
            dec current_mult
            bne mult_add_loop

mult_done_apply:
            rts

base_score:    !byte 0
current_mult:  !byte 0
score_add_lo:  !byte 0
score_add_hi:  !byte 0

; ----------------------------------------------------------------------------
; Add Score
; ----------------------------------------------------------------------------

add_score:
            lda score_lo
            clc
            adc score_add_lo
            sta score_lo
            lda score_hi
            adc score_add_hi
            sta score_hi
            rts

; ----------------------------------------------------------------------------
; Check and Update High Score
; ----------------------------------------------------------------------------
; Compares current score against high score for current song/difficulty.
; Sets new_high_score flag if current score is higher and updates table.

check_high_score:
            ; Clear new high score flag
            lda #0
            sta new_high_score

            ; Calculate table index: (selected_song * 3 + difficulty) * 2
            lda selected_song
            asl                     ; × 2
            clc
            adc selected_song       ; × 3
            clc
            adc difficulty          ; + difficulty
            asl                     ; × 2 (for 2-byte entries)
            tax                     ; X = table index

            ; Compare current score with high score
            ; First compare high bytes
            lda score_hi
            cmp high_scores+1,x     ; Compare high byte
            bcc hs_not_higher       ; Current < high, not new record
            bne hs_is_higher        ; Current > high, new record

            ; High bytes equal, compare low bytes
            lda score_lo
            cmp high_scores,x       ; Compare low byte
            bcc hs_not_higher       ; Current < high
            beq hs_not_higher       ; Current = high (not strictly greater)

hs_is_higher:
            ; New high score! Update table
            lda score_lo
            sta high_scores,x
            lda score_hi
            sta high_scores+1,x

            ; Set flag
            lda #1
            sta new_high_score

hs_not_higher:
            rts

; Get high score for current song/difficulty into work_lo/work_hi
get_high_score:
            ; Calculate table index: (selected_song * 3 + difficulty) * 2
            lda selected_song
            asl
            clc
            adc selected_song
            clc
            adc difficulty
            asl
            tax

            lda high_scores,x
            sta work_lo
            lda high_scores+1,x
            sta work_hi
            rts

; ----------------------------------------------------------------------------
; Display Score
; ----------------------------------------------------------------------------

display_score:
            lda score_lo
            sta work_lo
            lda score_hi
            sta work_hi

            ldx #0
div_10000:
            lda work_lo
            sec
            sbc #<10000
            tay
            lda work_hi
            sbc #>10000
            bcc done_10000
            sta work_hi
            sty work_lo
            inx
            jmp div_10000
done_10000:
            txa
            ora #$30
            sta SCREEN + 8

            ldx #0
div_1000:
            lda work_lo
            sec
            sbc #<1000
            tay
            lda work_hi
            sbc #>1000
            bcc done_1000
            sta work_hi
            sty work_lo
            inx
            jmp div_1000
done_1000:
            txa
            ora #$30
            sta SCREEN + 9

            ldx #0
div_100:
            lda work_lo
            sec
            sbc #100
            bcc done_100
            sta work_lo
            inx
            jmp div_100
done_100:
            txa
            ora #$30
            sta SCREEN + 10

            ldx #0
div_10:
            lda work_lo
            sec
            sbc #10
            bcc done_10
            sta work_lo
            inx
            jmp div_10
done_10:
            txa
            ora #$30
            sta SCREEN + 11

            lda work_lo
            ora #$30
            sta SCREEN + 12

            lda #7
            sta COLRAM + 8
            sta COLRAM + 9
            sta COLRAM + 10
            sta COLRAM + 11
            sta COLRAM + 12

            rts

; ----------------------------------------------------------------------------
; Display Misses
; ----------------------------------------------------------------------------

display_misses:
            lda miss_count

            ldx #0
miss_div_10:
            cmp #10
            bcc miss_done_10
            sec
            sbc #10
            inx
            jmp miss_div_10
miss_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + 21
            pla
            ora #$30
            sta SCREEN + 22

            lda #2
            sta COLRAM + 21
            sta COLRAM + 22

            rts

work_lo:    !byte 0
work_hi:    !byte 0

; ----------------------------------------------------------------------------
; Play Voices (for note playback)
; ----------------------------------------------------------------------------

play_voice1_note:
            lda #0
            sta SID_V1_FREQ_LO
            lda hit_note_freq
            sta SID_V1_FREQ_HI
            lda #VOICE1_WAVE
            ora #$01
            sta SID_V1_CTRL
            rts

play_voice2_note:
            lda #0
            sta SID_V2_FREQ_LO
            lda hit_note_freq
            sta SID_V2_FREQ_HI
            lda #VOICE2_WAVE
            ora #$01
            sta SID_V2_CTRL
            rts

play_voice3_note:
            lda #0
            sta SID_V3_FREQ_LO
            lda hit_note_freq
            sta SID_V3_FREQ_HI
            lda #VOICE3_WAVE
            ora #$01
            sta SID_V3_CTRL
            rts

; ----------------------------------------------------------------------------
; Flash Tracks
; ----------------------------------------------------------------------------

flash_track1_hit:
            ldx #0
            lda #HIT_COL
flash_t1h_loop:
            sta COLRAM + (TRACK1_ROW * 40),x
            inx
            cpx #38
            bne flash_t1h_loop
            lda #1
            sta COLRAM + (TRACK1_ROW * 40)
            rts

flash_track2_hit:
            ldx #0
            lda #HIT_COL
flash_t2h_loop:
            sta COLRAM + (TRACK2_ROW * 40),x
            inx
            cpx #38
            bne flash_t2h_loop
            lda #1
            sta COLRAM + (TRACK2_ROW * 40)
            rts

flash_track3_hit:
            ldx #0
            lda #HIT_COL
flash_t3h_loop:
            sta COLRAM + (TRACK3_ROW * 40),x
            inx
            cpx #38
            bne flash_t3h_loop
            lda #1
            sta COLRAM + (TRACK3_ROW * 40)
            rts

; ----------------------------------------------------------------------------
; Show Results Screen
; ----------------------------------------------------------------------------

show_results:
            ; Check if we beat the high score
            jsr check_high_score

            ; Clear screen
            ldx #0
            lda #CHAR_SPACE
clear_results:
            sta SCREEN,x
            sta SCREEN+$100,x
            sta SCREEN+$200,x
            sta SCREEN+$2E8,x
            inx
            bne clear_results

            ; Draw "SONG COMPLETE!"
            ldx #0
draw_complete:
            lda complete_text,x
            beq draw_results_score
            sta SCREEN + (5 * 40) + 13,x
            lda #5
            sta COLRAM + (5 * 40) + 13,x
            inx
            jmp draw_complete

draw_results_score:
            ; Draw score label
            ldx #0
draw_rs_label:
            lda results_score_label,x
            beq draw_rs_value
            sta SCREEN + (9 * 40) + 12,x
            lda #7
            sta COLRAM + (9 * 40) + 12,x
            inx
            jmp draw_rs_label

draw_rs_value:
            ; Draw score value
            lda score_lo
            sta work_lo
            lda score_hi
            sta work_hi

            ldx #0
rs_div_10000:
            lda work_lo
            sec
            sbc #<10000
            tay
            lda work_hi
            sbc #>10000
            bcc rs_done_10000
            sta work_hi
            sty work_lo
            inx
            jmp rs_div_10000
rs_done_10000:
            txa
            ora #$30
            sta SCREEN + (9 * 40) + 23

            ldx #0
rs_div_1000:
            lda work_lo
            sec
            sbc #<1000
            tay
            lda work_hi
            sbc #>1000
            bcc rs_done_1000
            sta work_hi
            sty work_lo
            inx
            jmp rs_div_1000
rs_done_1000:
            txa
            ora #$30
            sta SCREEN + (9 * 40) + 24

            ldx #0
rs_div_100:
            lda work_lo
            sec
            sbc #100
            bcc rs_done_100
            sta work_lo
            inx
            jmp rs_div_100
rs_done_100:
            txa
            ora #$30
            sta SCREEN + (9 * 40) + 25

            ldx #0
rs_div_10:
            lda work_lo
            sec
            sbc #10
            bcc rs_done_10
            sta work_lo
            inx
            jmp rs_div_10
rs_done_10:
            txa
            ora #$30
            sta SCREEN + (9 * 40) + 26

            lda work_lo
            ora #$30
            sta SCREEN + (9 * 40) + 27

            lda #7
            sta COLRAM + (9 * 40) + 23
            sta COLRAM + (9 * 40) + 24
            sta COLRAM + (9 * 40) + 25
            sta COLRAM + (9 * 40) + 26
            sta COLRAM + (9 * 40) + 27

            ; Draw perfect count
            ldx #0
draw_perfect_label:
            lda perfect_label,x
            beq draw_perfect_value
            sta SCREEN + (11 * 40) + 12,x
            lda #1
            sta COLRAM + (11 * 40) + 12,x
            inx
            jmp draw_perfect_label

draw_perfect_value:
            lda perfect_count
            ldx #0
pv_div_10:
            cmp #10
            bcc pv_done_10
            sec
            sbc #10
            inx
            jmp pv_div_10
pv_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + (11 * 40) + 23
            pla
            ora #$30
            sta SCREEN + (11 * 40) + 24
            lda #1
            sta COLRAM + (11 * 40) + 23
            sta COLRAM + (11 * 40) + 24

            ; Draw good count
            ldx #0
draw_good_label:
            lda good_label,x
            beq draw_good_value
            sta SCREEN + (12 * 40) + 12,x
            lda #7
            sta COLRAM + (12 * 40) + 12,x
            inx
            jmp draw_good_label

draw_good_value:
            lda good_count
            ldx #0
gv_div_10:
            cmp #10
            bcc gv_done_10
            sec
            sbc #10
            inx
            jmp gv_div_10
gv_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + (12 * 40) + 23
            pla
            ora #$30
            sta SCREEN + (12 * 40) + 24
            lda #7
            sta COLRAM + (12 * 40) + 23
            sta COLRAM + (12 * 40) + 24

            ; Draw miss count
            ldx #0
draw_miss_label_r:
            lda miss_label_r,x
            beq draw_miss_value
            sta SCREEN + (13 * 40) + 12,x
            lda #2
            sta COLRAM + (13 * 40) + 12,x
            inx
            jmp draw_miss_label_r

draw_miss_value:
            lda miss_count
            ldx #0
mv_div_10:
            cmp #10
            bcc mv_done_10
            sec
            sbc #10
            inx
            jmp mv_div_10
mv_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + (13 * 40) + 23
            pla
            ora #$30
            sta SCREEN + (13 * 40) + 24
            lda #2
            sta COLRAM + (13 * 40) + 23
            sta COLRAM + (13 * 40) + 24

            ; Draw max combo
            ldx #0
draw_maxc_label:
            lda maxcombo_label,x
            beq draw_maxc_value
            sta SCREEN + (15 * 40) + 12,x
            lda #COMBO_COL
            sta COLRAM + (15 * 40) + 12,x
            inx
            jmp draw_maxc_label

draw_maxc_value:
            lda max_combo
            ldx #0
mc_div_100:
            cmp #100
            bcc mc_done_100
            sec
            sbc #100
            inx
            jmp mc_div_100
mc_done_100:
            pha
            txa
            ora #$30
            sta SCREEN + (15 * 40) + 23

            pla
            ldx #0
mc_div_10:
            cmp #10
            bcc mc_done_10
            sec
            sbc #10
            inx
            jmp mc_div_10
mc_done_10:
            pha
            txa
            ora #$30
            sta SCREEN + (15 * 40) + 24
            pla
            ora #$30
            sta SCREEN + (15 * 40) + 25
            lda #COMBO_COL
            sta COLRAM + (15 * 40) + 23
            sta COLRAM + (15 * 40) + 24
            sta COLRAM + (15 * 40) + 25

            ; Check if this was a new high score
            lda new_high_score
            beq res_show_prev_hs

            ; Draw "NEW HIGH SCORE!" in bright cyan
            ldx #0
res_draw_new_hs:
            lda new_hs_text,x
            bne +                   ; Branch over jump if not zero
            jmp res_draw_return     ; Far jump when zero
+           sta SCREEN + (17 * 40) + 12,x
            lda #3                  ; Cyan
            sta COLRAM + (17 * 40) + 12,x
            inx
            jmp res_draw_new_hs

res_show_prev_hs:
            ; Draw "HIGH SCORE:" label
            ldx #0
res_draw_hs_label:
            lda high_score_text,x
            beq res_draw_hs_value
            sta SCREEN + (17 * 40) + 12,x
            lda #11                 ; Dark grey
            sta COLRAM + (17 * 40) + 12,x
            inx
            jmp res_draw_hs_label

res_draw_hs_value:
            ; Get high score for current song/difficulty
            jsr get_high_score

            ; Display 5-digit high score
            ldx #0
res_hs_div_10000:
            lda work_lo
            sec
            sbc #<10000
            tay
            lda work_hi
            sbc #>10000
            bcc res_hs_done_10000
            sta work_hi
            sty work_lo
            inx
            jmp res_hs_div_10000
res_hs_done_10000:
            txa
            ora #$30
            sta SCREEN + (17 * 40) + 24

            ldx #0
res_hs_div_1000:
            lda work_lo
            sec
            sbc #<1000
            tay
            lda work_hi
            sbc #>1000
            bcc res_hs_done_1000
            sta work_hi
            sty work_lo
            inx
            jmp res_hs_div_1000
res_hs_done_1000:
            txa
            ora #$30
            sta SCREEN + (17 * 40) + 25

            ldx #0
res_hs_div_100:
            lda work_lo
            sec
            sbc #100
            bcc res_hs_done_100
            sta work_lo
            inx
            jmp res_hs_div_100
res_hs_done_100:
            txa
            ora #$30
            sta SCREEN + (17 * 40) + 26

            ldx #0
res_hs_div_10:
            lda work_lo
            sec
            sbc #10
            bcc res_hs_done_10
            sta work_lo
            inx
            jmp res_hs_div_10
res_hs_done_10:
            txa
            ora #$30
            sta SCREEN + (17 * 40) + 27

            lda work_lo
            ora #$30
            sta SCREEN + (17 * 40) + 28

            ; Colour high score digits
            lda #11
            sta COLRAM + (17 * 40) + 24
            sta COLRAM + (17 * 40) + 25
            sta COLRAM + (17 * 40) + 26
            sta COLRAM + (17 * 40) + 27
            sta COLRAM + (17 * 40) + 28

res_draw_return:
            ; Draw "PRESS FIRE"
            ldx #0
draw_return:
            lda return_text,x
            beq results_done
            sta SCREEN + (20 * 40) + 10,x
            lda #11
            sta COLRAM + (20 * 40) + 10,x
            inx
            jmp draw_return

results_done:
            rts

complete_text:
            !scr "song complete!"
            !byte 0

results_score_label:
            !scr "final score:"
            !byte 0

perfect_label:
            !scr "perfect:"
            !byte 0

good_label:
            !scr "good:"
            !byte 0

miss_label_r:
            !scr "misses:"
            !byte 0

maxcombo_label:
            !scr "max combo:"
            !byte 0

return_text:
            !scr "press fire to continue"
            !byte 0

; ----------------------------------------------------------------------------
; Show Game Over Screen
; ----------------------------------------------------------------------------

show_gameover:
            ; Check if we beat the high score
            jsr check_high_score

            ; Clear screen
            ldx #0
            lda #CHAR_SPACE
clear_gameover:
            sta SCREEN,x
            sta SCREEN+$100,x
            sta SCREEN+$200,x
            sta SCREEN+$2E8,x
            inx
            bne clear_gameover

            ; Draw "GAME OVER"
            ldx #0
draw_gameover_text:
            lda gameover_text,x
            beq draw_gameover_score
            sta SCREEN + (8 * 40) + 15,x
            lda #2
            sta COLRAM + (8 * 40) + 15,x
            inx
            jmp draw_gameover_text

draw_gameover_score:
            ; Draw score
            ldx #0
draw_go_score_label:
            lda gameover_score,x
            beq draw_go_score_value
            sta SCREEN + (12 * 40) + 12,x
            lda #7
            sta COLRAM + (12 * 40) + 12,x
            inx
            jmp draw_go_score_label

draw_go_score_value:
            lda score_lo
            sta work_lo
            lda score_hi
            sta work_hi

            ldx #0
go_div_10000:
            lda work_lo
            sec
            sbc #<10000
            tay
            lda work_hi
            sbc #>10000
            bcc go_done_10000
            sta work_hi
            sty work_lo
            inx
            jmp go_div_10000
go_done_10000:
            txa
            ora #$30
            sta SCREEN + (12 * 40) + 23

            ldx #0
go_div_1000:
            lda work_lo
            sec
            sbc #<1000
            tay
            lda work_hi
            sbc #>1000
            bcc go_done_1000
            sta work_hi
            sty work_lo
            inx
            jmp go_div_1000
go_done_1000:
            txa
            ora #$30
            sta SCREEN + (12 * 40) + 24

            ldx #0
go_div_100:
            lda work_lo
            sec
            sbc #100
            bcc go_done_100
            sta work_lo
            inx
            jmp go_div_100
go_done_100:
            txa
            ora #$30
            sta SCREEN + (12 * 40) + 25

            ldx #0
go_div_10:
            lda work_lo
            sec
            sbc #10
            bcc go_done_10
            sta work_lo
            inx
            jmp go_div_10
go_done_10:
            txa
            ora #$30
            sta SCREEN + (12 * 40) + 26

            lda work_lo
            ora #$30
            sta SCREEN + (12 * 40) + 27

            lda #7
            sta COLRAM + (12 * 40) + 23
            sta COLRAM + (12 * 40) + 24
            sta COLRAM + (12 * 40) + 25
            sta COLRAM + (12 * 40) + 26
            sta COLRAM + (12 * 40) + 27

            ; Check if this was a new high score
            lda new_high_score
            beq draw_prev_high

            ; Draw "NEW HIGH SCORE!" in bright cyan
            ldx #0
draw_new_hs:
            lda new_hs_text,x
            bne +                   ; Branch over jump if not zero
            jmp go_draw_retry       ; Far jump when zero
+           sta SCREEN + (14 * 40) + 12,x
            lda #3                  ; Cyan
            sta COLRAM + (14 * 40) + 12,x
            inx
            jmp draw_new_hs

draw_prev_high:
            ; Draw "HIGH SCORE:" label
            ldx #0
draw_hs_label:
            lda high_score_text,x
            beq draw_hs_value
            sta SCREEN + (14 * 40) + 12,x
            lda #11                 ; Dark grey
            sta COLRAM + (14 * 40) + 12,x
            inx
            jmp draw_hs_label

draw_hs_value:
            ; Get current high score into work_lo/work_hi
            jsr get_high_score

            ; Draw 5-digit high score value
            ldx #0
hs_div_10000:
            lda work_lo
            sec
            sbc #<10000
            tay
            lda work_hi
            sbc #>10000
            bcc hs_done_10000
            sta work_hi
            sty work_lo
            inx
            jmp hs_div_10000
hs_done_10000:
            txa
            ora #$30
            sta SCREEN + (14 * 40) + 24

            ldx #0
hs_div_1000:
            lda work_lo
            sec
            sbc #<1000
            tay
            lda work_hi
            sbc #>1000
            bcc hs_done_1000
            sta work_hi
            sty work_lo
            inx
            jmp hs_div_1000
hs_done_1000:
            txa
            ora #$30
            sta SCREEN + (14 * 40) + 25

            ldx #0
hs_div_100:
            lda work_lo
            sec
            sbc #100
            bcc hs_done_100
            sta work_lo
            inx
            jmp hs_div_100
hs_done_100:
            txa
            ora #$30
            sta SCREEN + (14 * 40) + 26

            ldx #0
hs_div_10:
            lda work_lo
            sec
            sbc #10
            bcc hs_done_10
            sta work_lo
            inx
            jmp hs_div_10
hs_done_10:
            txa
            ora #$30
            sta SCREEN + (14 * 40) + 27

            lda work_lo
            ora #$30
            sta SCREEN + (14 * 40) + 28

            ; Colour high score digits
            lda #11
            sta COLRAM + (14 * 40) + 24
            sta COLRAM + (14 * 40) + 25
            sta COLRAM + (14 * 40) + 26
            sta COLRAM + (14 * 40) + 27
            sta COLRAM + (14 * 40) + 28

go_draw_retry:
            ; Draw retry message
            ldx #0
draw_retry:
            lda retry_text,x
            beq gameover_done
            sta SCREEN + (18 * 40) + 10,x
            lda #11
            sta COLRAM + (18 * 40) + 10,x
            inx
            jmp draw_retry

gameover_done:
            rts

gameover_text:
            !scr "game over"
            !byte 0

gameover_score:
            !scr "your score:"
            !byte 0

new_hs_text:
            !scr "new high score!"
            !byte 0

high_score_text:
            !scr "high score:"
            !byte 0

retry_text:
            !scr "press fire to continue"
            !byte 0

; ============================================================================
; SONG 1 DATA - "First Steps" (120 BPM) - Three Difficulty Variants
; ============================================================================
; Easy: Notes only on strong beats (0, 8, 16, 24...) - 8 notes
; Normal: Base pattern - 29 notes
; Hard: Dense pattern with off-beat additions - 45 notes

; --- EASY: Sparse pattern (strong beats only) ---
song1_easy:
            !byte 0, 1, $47          ; Beat 0
            !byte 8, 2, $27          ; Beat 8
            !byte 16, 1, $35         ; Beat 16
            !byte 24, 3, $11         ; Beat 24
            !byte 32, 2, $2F         ; Beat 32
            !byte 40, 1, $58         ; Beat 40
            !byte 48, 3, $1A         ; Beat 48
            !byte 56, 1, $47         ; Beat 56
            !byte $FF

; --- NORMAL: Base pattern ---
song1_normal:
            !byte 0, 1, $47
            !byte 2, 2, $2C
            !byte 4, 3, $11
            !byte 8, 1, $3B
            !byte 10, 2, $27
            !byte 12, 3, $13
            !byte 16, 1, $35
            !byte 17, 2, $2C
            !byte 18, 1, $3B
            !byte 20, 3, $16
            !byte 24, 1, $47
            !byte 26, 2, $35
            !byte 28, 3, $11
            !byte 32, 2, $2F
            !byte 34, 1, $4F
            !byte 36, 3, $17
            !byte 40, 1, $58
            !byte 42, 2, $2C
            !byte 44, 3, $11
            !byte 46, 2, $27
            !byte 48, 1, $6A
            !byte 49, 2, $35
            !byte 50, 1, $58
            !byte 52, 3, $1A
            !byte 54, 2, $2F
            !byte 56, 1, $47
            !byte 58, 2, $2C
            !byte 60, 3, $11
            !byte 62, 1, $35
            !byte $FF

; --- HARD: Dense pattern (added off-beats) ---
song1_hard:
            !byte 0, 1, $47
            !byte 1, 3, $16          ; Added
            !byte 2, 2, $2C
            !byte 3, 1, $35          ; Added
            !byte 4, 3, $11
            !byte 5, 2, $27          ; Added
            !byte 6, 1, $3B          ; Added
            !byte 8, 1, $3B
            !byte 9, 3, $13          ; Added
            !byte 10, 2, $27
            !byte 11, 1, $35         ; Added
            !byte 12, 3, $13
            !byte 14, 2, $2C         ; Added
            !byte 16, 1, $35
            !byte 17, 2, $2C
            !byte 18, 1, $3B
            !byte 19, 3, $11         ; Added
            !byte 20, 3, $16
            !byte 21, 1, $47         ; Added
            !byte 22, 2, $35         ; Added
            !byte 24, 1, $47
            !byte 25, 3, $16         ; Added
            !byte 26, 2, $35
            !byte 27, 1, $4F         ; Added
            !byte 28, 3, $11
            !byte 30, 2, $27         ; Added
            !byte 32, 2, $2F
            !byte 33, 1, $47         ; Added
            !byte 34, 1, $4F
            !byte 35, 3, $11         ; Added
            !byte 36, 3, $17
            !byte 38, 2, $2C         ; Added
            !byte 40, 1, $58
            !byte 41, 3, $1A         ; Added
            !byte 42, 2, $2C
            !byte 43, 1, $47         ; Added
            !byte 44, 3, $11
            !byte 45, 2, $35         ; Added
            !byte 46, 2, $27
            !byte 47, 1, $4F         ; Added
            !byte 48, 1, $6A
            !byte 49, 2, $35
            !byte 50, 1, $58
            !byte 51, 3, $16         ; Added
            !byte 52, 3, $1A
            !byte 53, 1, $47         ; Added
            !byte 54, 2, $2F
            !byte 55, 3, $11         ; Added
            !byte 56, 1, $47
            !byte 57, 2, $27         ; Added
            !byte 58, 2, $2C
            !byte 59, 1, $3B         ; Added
            !byte 60, 3, $11
            !byte 61, 2, $35         ; Added
            !byte 62, 1, $35
            !byte 63, 3, $16         ; Added
            !byte $FF

; ============================================================================
; SONG 2 DATA - "Upbeat Groove" (130 BPM) - Three Difficulty Variants
; ============================================================================
; Easy: Notes only on strong beats - 8 notes
; Normal: Base syncopated pattern - 52 notes
; Hard: Extremely dense pattern - 72 notes

; --- EASY: Sparse pattern (strong beats only) ---
song2_easy:
            !byte 0, 1, $47          ; Beat 0
            !byte 8, 3, $11          ; Beat 8
            !byte 16, 1, $4F         ; Beat 16
            !byte 24, 2, $47         ; Beat 24
            !byte 32, 1, $4F         ; Beat 32
            !byte 40, 3, $1A         ; Beat 40
            !byte 48, 3, $11         ; Beat 48
            !byte 56, 1, $47         ; Beat 56
            !byte $FF

; --- NORMAL: Base syncopated pattern ---
song2_normal:
            !byte 0, 1, $47
            !byte 1, 2, $35
            !byte 3, 3, $16
            !byte 4, 1, $4F
            !byte 5, 2, $2C
            !byte 7, 1, $47
            !byte 8, 3, $11
            !byte 10, 2, $35
            !byte 11, 1, $58
            !byte 13, 2, $2C
            !byte 14, 3, $1A
            !byte 15, 1, $47
            !byte 16, 1, $4F
            !byte 17, 2, $35
            !byte 18, 3, $16
            !byte 19, 1, $58
            !byte 20, 2, $2C
            !byte 22, 1, $6A
            !byte 23, 2, $35
            !byte 24, 3, $11
            !byte 25, 1, $58
            !byte 26, 2, $47
            !byte 28, 3, $1A
            !byte 30, 1, $47
            !byte 31, 2, $2C
            !byte 32, 1, $4F
            !byte 33, 3, $16
            !byte 34, 2, $35
            !byte 35, 1, $58
            !byte 36, 3, $11
            !byte 37, 1, $6A
            !byte 38, 2, $47
            !byte 39, 1, $58
            !byte 40, 3, $1A
            !byte 41, 2, $35
            !byte 42, 1, $4F
            !byte 43, 2, $2C
            !byte 44, 1, $47
            !byte 45, 3, $16
            !byte 46, 2, $35
            !byte 47, 1, $58
            !byte 48, 3, $11
            !byte 49, 2, $47
            !byte 51, 1, $4F
            !byte 52, 3, $1A
            !byte 54, 2, $35
            !byte 55, 1, $47
            !byte 56, 3, $11
            !byte 58, 2, $2C
            !byte 59, 1, $58
            !byte 60, 3, $16
            !byte 61, 2, $35
            !byte 62, 1, $47
            !byte $FF

; --- HARD: Extremely dense pattern ---
song2_hard:
            !byte 0, 1, $47
            !byte 0, 3, $11          ; Chord
            !byte 1, 2, $35
            !byte 2, 1, $4F          ; Added
            !byte 3, 3, $16
            !byte 4, 1, $4F
            !byte 4, 2, $2C          ; Chord
            !byte 5, 2, $2C
            !byte 6, 3, $1A          ; Added
            !byte 7, 1, $47
            !byte 8, 3, $11
            !byte 8, 1, $58          ; Chord
            !byte 9, 2, $35          ; Added
            !byte 10, 2, $35
            !byte 11, 1, $58
            !byte 12, 3, $16         ; Added
            !byte 13, 2, $2C
            !byte 14, 3, $1A
            !byte 15, 1, $47
            !byte 16, 1, $4F
            !byte 16, 3, $11         ; Chord
            !byte 17, 2, $35
            !byte 18, 3, $16
            !byte 19, 1, $58
            !byte 20, 2, $2C
            !byte 20, 1, $47         ; Chord
            !byte 21, 3, $1A         ; Added
            !byte 22, 1, $6A
            !byte 23, 2, $35
            !byte 24, 3, $11
            !byte 24, 1, $4F         ; Chord
            !byte 25, 1, $58
            !byte 26, 2, $47
            !byte 27, 3, $16         ; Added
            !byte 28, 3, $1A
            !byte 28, 1, $58         ; Chord
            !byte 29, 2, $35         ; Added
            !byte 30, 1, $47
            !byte 31, 2, $2C
            !byte 32, 1, $4F
            !byte 32, 3, $11         ; Chord
            !byte 33, 3, $16
            !byte 34, 2, $35
            !byte 35, 1, $58
            !byte 36, 3, $11
            !byte 36, 2, $47         ; Chord
            !byte 37, 1, $6A
            !byte 38, 2, $47
            !byte 39, 1, $58
            !byte 40, 3, $1A
            !byte 40, 1, $4F         ; Chord
            !byte 41, 2, $35
            !byte 42, 1, $4F
            !byte 43, 2, $2C
            !byte 44, 1, $47
            !byte 44, 3, $11         ; Chord
            !byte 45, 3, $16
            !byte 46, 2, $35
            !byte 47, 1, $58
            !byte 48, 3, $11
            !byte 48, 1, $6A         ; Chord
            !byte 49, 2, $47
            !byte 50, 1, $58         ; Added
            !byte 51, 1, $4F
            !byte 52, 3, $1A
            !byte 52, 2, $35         ; Chord
            !byte 53, 1, $47         ; Added
            !byte 54, 2, $35
            !byte 55, 1, $47
            !byte 56, 3, $11
            !byte 56, 1, $4F         ; Chord
            !byte 57, 2, $47         ; Added
            !byte 58, 2, $2C
            !byte 59, 1, $58
            !byte 60, 3, $16
            !byte 60, 1, $47         ; Chord
            !byte 61, 2, $35
            !byte 62, 1, $47
            !byte 63, 3, $11         ; Added
            !byte $FF

; ============================================================================
; SONG 3 DATA: "Speed Rush" (150 BPM)
; ============================================================================
; An energetic, fast-paced track designed to test reaction time.
; Higher frequencies and rapid note sequences.

; --- EASY: Strong beats only (8 notes) ---
song3_easy:
            !byte 0, 1, $58          ; Beat 0
            !byte 8, 2, $35          ; Beat 8
            !byte 16, 3, $1A         ; Beat 16
            !byte 24, 1, $6A         ; Beat 24
            !byte 32, 2, $47         ; Beat 32
            !byte 40, 3, $16         ; Beat 40
            !byte 48, 1, $58         ; Beat 48
            !byte 56, 2, $35         ; Beat 56
            !byte $FF

; --- NORMAL: Base pattern (32 notes) ---
song3_normal:
            !byte 0, 1, $58
            !byte 2, 2, $35
            !byte 4, 3, $1A
            !byte 6, 1, $6A
            !byte 8, 2, $35
            !byte 10, 1, $58
            !byte 12, 3, $16
            !byte 14, 2, $47
            !byte 16, 3, $1A
            !byte 18, 1, $6A
            !byte 20, 2, $35
            !byte 22, 3, $16
            !byte 24, 1, $6A
            !byte 26, 2, $47
            !byte 28, 3, $1A
            !byte 30, 1, $58
            !byte 32, 2, $47
            !byte 34, 1, $58
            !byte 36, 3, $16
            !byte 38, 2, $35
            !byte 40, 3, $16
            !byte 42, 1, $6A
            !byte 44, 2, $47
            !byte 46, 3, $1A
            !byte 48, 1, $58
            !byte 50, 2, $35
            !byte 52, 3, $16
            !byte 54, 1, $6A
            !byte 56, 2, $35
            !byte 58, 3, $1A
            !byte 60, 1, $58
            !byte 62, 2, $47
            !byte $FF

; --- HARD: Dense pattern with rapid-fire sections (56 notes) ---
song3_hard:
            !byte 0, 1, $58
            !byte 1, 3, $1A          ; Added
            !byte 2, 2, $35
            !byte 3, 1, $6A          ; Added
            !byte 4, 3, $1A
            !byte 5, 2, $47          ; Added
            !byte 6, 1, $6A
            !byte 7, 3, $16          ; Added
            !byte 8, 2, $35
            !byte 9, 1, $58          ; Added
            !byte 10, 1, $58
            !byte 11, 2, $35         ; Added
            !byte 12, 3, $16
            !byte 13, 1, $6A         ; Added
            !byte 14, 2, $47
            !byte 15, 3, $1A         ; Added
            !byte 16, 3, $1A
            !byte 17, 1, $58         ; Added
            !byte 18, 1, $6A
            !byte 19, 2, $35         ; Added
            !byte 20, 2, $35
            !byte 21, 3, $16         ; Added
            !byte 22, 3, $16
            !byte 23, 1, $58         ; Added
            !byte 24, 1, $6A
            !byte 25, 2, $47         ; Added
            !byte 26, 2, $47
            !byte 27, 3, $1A         ; Added
            !byte 28, 3, $1A
            !byte 29, 1, $6A         ; Added
            !byte 30, 1, $58
            !byte 31, 2, $35         ; Added
            !byte 32, 2, $47
            !byte 33, 3, $16         ; Added
            !byte 34, 1, $58
            !byte 35, 2, $47         ; Added
            !byte 36, 3, $16
            !byte 37, 1, $6A         ; Added
            !byte 38, 2, $35
            !byte 39, 3, $1A         ; Added
            !byte 40, 3, $16
            !byte 41, 1, $58         ; Added
            !byte 42, 1, $6A
            !byte 43, 2, $35         ; Added
            !byte 44, 2, $47
            !byte 45, 3, $16         ; Added
            !byte 46, 3, $1A
            !byte 47, 1, $6A         ; Added
            !byte 48, 1, $58
            !byte 49, 2, $47         ; Added
            !byte 50, 2, $35
            !byte 51, 3, $1A         ; Added
            !byte 52, 3, $16
            !byte 53, 1, $58         ; Added
            !byte 54, 1, $6A
            !byte 55, 2, $35         ; Added
            !byte 56, 2, $35
            !byte 57, 3, $16         ; Added
            !byte 58, 3, $1A
            !byte 59, 1, $6A         ; Added
            !byte 60, 1, $58
            !byte 61, 2, $47         ; Added
            !byte 62, 2, $47
            !byte 63, 3, $1A         ; Added
            !byte $FF

; ============================================================================
; SONG 4: "Off-Beat" (125 BPM) - Syncopated rhythms
; ============================================================================
; Syncopation emphasises off-beats. Notes land between expected beats,
; challenging players' sense of rhythm. The pattern feels "pushed" forward.

; --- EASY: Sparse syncopated notes (10 notes) ---
; Only the most prominent off-beat accents
song4_easy:
            !byte 1, 1, $47          ; Off-beat accent
            !byte 9, 2, $3B          ; Pushed note
            !byte 17, 3, $27         ; Syncopated hit
            !byte 25, 1, $47         ; Off-beat
            !byte 33, 2, $3B         ; Pushed
            !byte 41, 3, $27         ; Syncopated
            !byte 49, 1, $47         ; Off-beat
            !byte 55, 2, $3B         ; Pushed
            !byte 59, 3, $27         ; Syncopated
            !byte 63, 1, $47         ; Final accent
            !byte $FF

; --- NORMAL: Syncopated pattern with anchors (32 notes) ---
; Mix of on-beat anchors and off-beat accents
song4_normal:
            !byte 0, 1, $47          ; Anchor
            !byte 1, 2, $3B          ; Off-beat
            !byte 3, 3, $27          ; Syncopated
            !byte 4, 1, $47          ; Anchor
            !byte 5, 2, $3B          ; Off-beat
            !byte 7, 3, $27          ; Syncopated
            !byte 8, 1, $47          ; Anchor
            !byte 9, 2, $3B          ; Off-beat
            !byte 11, 3, $27         ; Syncopated
            !byte 12, 1, $47         ; Anchor
            !byte 13, 2, $3B         ; Off-beat
            !byte 15, 3, $27         ; Syncopated
            !byte 16, 1, $47         ; Anchor
            !byte 17, 2, $3B         ; Off-beat
            !byte 19, 3, $27         ; Syncopated
            !byte 20, 1, $47         ; Anchor
            !byte 21, 2, $3B         ; Off-beat
            !byte 23, 3, $27         ; Syncopated
            !byte 24, 1, $47         ; Anchor
            !byte 25, 2, $3B         ; Off-beat
            !byte 27, 3, $27         ; Syncopated
            !byte 28, 1, $47         ; Anchor
            !byte 29, 2, $3B         ; Off-beat
            !byte 31, 3, $27         ; Syncopated
            !byte 32, 1, $47         ; Anchor
            !byte 33, 2, $3B         ; Off-beat
            !byte 35, 3, $27         ; Syncopated
            !byte 40, 1, $47         ; Anchor
            !byte 41, 2, $3B         ; Off-beat
            !byte 48, 1, $47         ; Anchor
            !byte 49, 3, $27         ; Off-beat
            !byte 56, 1, $47         ; Final anchor
            !byte $FF

; --- HARD: Dense syncopated chaos (56 notes) ---
; Nearly every off-beat filled, minimal anchors
song4_hard:
            !byte 0, 1, $47          ; Anchor
            !byte 1, 2, $3B          ; Off-beat
            !byte 1, 3, $27          ; Chord
            !byte 3, 1, $47          ; Syncopated
            !byte 3, 2, $3B          ; Chord
            !byte 5, 3, $27          ; Off-beat
            !byte 5, 1, $47          ; Chord
            !byte 7, 2, $3B          ; Syncopated
            !byte 7, 3, $27          ; Chord
            !byte 8, 1, $47          ; Anchor
            !byte 9, 2, $3B          ; Off-beat
            !byte 9, 3, $27          ; Chord
            !byte 11, 1, $47         ; Syncopated
            !byte 11, 2, $3B         ; Chord
            !byte 13, 3, $27         ; Off-beat
            !byte 13, 1, $47         ; Chord
            !byte 15, 2, $3B         ; Syncopated
            !byte 15, 3, $27         ; Chord
            !byte 16, 1, $47         ; Anchor
            !byte 17, 2, $3B         ; Off-beat
            !byte 17, 3, $27         ; Chord
            !byte 19, 1, $47         ; Syncopated
            !byte 19, 2, $3B         ; Chord
            !byte 21, 3, $27         ; Off-beat
            !byte 21, 1, $47         ; Chord
            !byte 23, 2, $3B         ; Syncopated
            !byte 23, 3, $27         ; Chord
            !byte 24, 1, $47         ; Anchor
            !byte 25, 2, $3B         ; Off-beat
            !byte 25, 3, $27         ; Chord
            !byte 27, 1, $47         ; Syncopated
            !byte 27, 2, $3B         ; Chord
            !byte 29, 3, $27         ; Off-beat
            !byte 29, 1, $47         ; Chord
            !byte 31, 2, $3B         ; Syncopated
            !byte 31, 3, $27         ; Chord
            !byte 32, 1, $47         ; Anchor
            !byte 33, 2, $3B         ; Off-beat
            !byte 35, 3, $27         ; Syncopated
            !byte 37, 1, $47         ; Off-beat
            !byte 39, 2, $3B         ; Syncopated
            !byte 40, 1, $47         ; Anchor
            !byte 41, 3, $27         ; Off-beat
            !byte 43, 2, $3B         ; Syncopated
            !byte 45, 1, $47         ; Off-beat
            !byte 47, 3, $27         ; Syncopated
            !byte 48, 1, $47         ; Anchor
            !byte 49, 2, $3B         ; Off-beat
            !byte 51, 3, $27         ; Syncopated
            !byte 53, 1, $47         ; Off-beat
            !byte 55, 2, $3B         ; Syncopated
            !byte 56, 1, $47         ; Anchor
            !byte 57, 3, $27         ; Off-beat
            !byte 59, 2, $3B         ; Syncopated
            !byte 61, 1, $47         ; Off-beat
            !byte 63, 3, $27         ; Final syncopated
            !byte $FF

; ----------------------------------------------------------------------------
; Note Arrays
; ----------------------------------------------------------------------------

note_track:
            !fill MAX_NOTES, 0

note_col:
            !fill MAX_NOTES, 0

note_freq:
            !fill MAX_NOTES, 0

; ----------------------------------------------------------------------------
; Game Variables
; ----------------------------------------------------------------------------

score_lo:     !byte 0
score_hi:     !byte 0
miss_count:   !byte 0
perfect_count: !byte 0
good_count:   !byte 0
health:       !byte 0
combo:        !byte 0
max_combo:    !byte 0
new_high_score: !byte 0          ; Flag: 1 if current score beat high score

; ----------------------------------------------------------------------------
; High Score Table (4 songs x 3 difficulties = 12 entries, 2 bytes each)
; Index = (song * 3) + difficulty
; ----------------------------------------------------------------------------

high_scores:
            ; Song 1 (First Steps)
            !word 0               ; Easy high score
            !word 0               ; Normal high score
            !word 0               ; Hard high score
            ; Song 2 (Upbeat Groove)
            !word 0               ; Easy
            !word 0               ; Normal
            !word 0               ; Hard
            ; Song 3 (Speed Rush)
            !word 0               ; Easy
            !word 0               ; Normal
            !word 0               ; Hard
            ; Song 4 (Off-Beat)
            !word 0               ; Easy
            !word 0               ; Normal
            !word 0               ; Hard

; ============================================================================
; END OF SID SYMPHONY - UNIT 25
; ============================================================================

What’s Coming

With high score tracking motivating replay:

  • Unit 26: Song 5 with complex patterns
  • Unit 27: Visual polish and effects
  • Unit 28: Additional game modes

What You’ve Learnt

  • Data tables - Storing multiple values in indexed arrays
  • Index calculation - Converting 2D coordinates to 1D offset
  • Multi-byte comparison - Comparing 16-bit values correctly
  • Branch trampolines - Working around branch distance limits
  • State flags - Using single bytes to control display logic
  • Persistence scope - Session vs. disk storage trade-offs

High scores give players a reason to return.

What Changed

Unit 24 → Unit 25
+330-6
11 ; ============================================================================
2-; SID SYMPHONY - Unit 24: Song 4 - Syncopation
2+; SID SYMPHONY - Unit 25: High Score Persistence
33 ; ============================================================================
4-; Adding a fourth song that emphasises off-beats. Notes land between expected
5-; beats, challenging players' rhythm intuition. A visual beat marker pulses
6-; on downbeats to help players stay oriented.
4+; Adding high score tracking that persists across plays within a session.
5+; Each song/difficulty combination tracks its own high score. Beating a high
6+; score triggers a "NEW HIGH SCORE" celebration.
77 ;
8-; New concepts: Syncopation, off-beat patterns, visual beat indicator
8+; New concepts: Score comparison, multi-byte arithmetic, high score tables
99 ;
1010 ; Controls: Z = Track 1, X = Track 2, C = Track 3
1111 ; Up/Down = Song selection, Left/Right = Difficulty
...
29442944 lda score_hi
29452945 adc score_add_hi
29462946 sta score_hi
2947+ rts
2948+
2949+; ----------------------------------------------------------------------------
2950+; Check and Update High Score
2951+; ----------------------------------------------------------------------------
2952+; Compares current score against high score for current song/difficulty.
2953+; Sets new_high_score flag if current score is higher and updates table.
2954+
2955+check_high_score:
2956+ ; Clear new high score flag
2957+ lda #0
2958+ sta new_high_score
2959+
2960+ ; Calculate table index: (selected_song * 3 + difficulty) * 2
2961+ lda selected_song
2962+ asl ; × 2
2963+ clc
2964+ adc selected_song ; × 3
2965+ clc
2966+ adc difficulty ; + difficulty
2967+ asl ; × 2 (for 2-byte entries)
2968+ tax ; X = table index
2969+
2970+ ; Compare current score with high score
2971+ ; First compare high bytes
2972+ lda score_hi
2973+ cmp high_scores+1,x ; Compare high byte
2974+ bcc hs_not_higher ; Current < high, not new record
2975+ bne hs_is_higher ; Current > high, new record
2976+
2977+ ; High bytes equal, compare low bytes
2978+ lda score_lo
2979+ cmp high_scores,x ; Compare low byte
2980+ bcc hs_not_higher ; Current < high
2981+ beq hs_not_higher ; Current = high (not strictly greater)
2982+
2983+hs_is_higher:
2984+ ; New high score! Update table
2985+ lda score_lo
2986+ sta high_scores,x
2987+ lda score_hi
2988+ sta high_scores+1,x
2989+
2990+ ; Set flag
2991+ lda #1
2992+ sta new_high_score
2993+
2994+hs_not_higher:
2995+ rts
2996+
2997+; Get high score for current song/difficulty into work_lo/work_hi
2998+get_high_score:
2999+ ; Calculate table index: (selected_song * 3 + difficulty) * 2
3000+ lda selected_song
3001+ asl
3002+ clc
3003+ adc selected_song
3004+ clc
3005+ adc difficulty
3006+ asl
3007+ tax
3008+
3009+ lda high_scores,x
3010+ sta work_lo
3011+ lda high_scores+1,x
3012+ sta work_hi
29473013 rts
29483014
29493015 ; ----------------------------------------------------------------------------
...
31453211 ; ----------------------------------------------------------------------------
31463212
31473213 show_results:
3214+ ; Check if we beat the high score
3215+ jsr check_high_score
3216+
31483217 ; Clear screen
31493218 ldx #0
31503219 lda #CHAR_SPACE
...
34083477 sta COLRAM + (15 * 40) + 23
34093478 sta COLRAM + (15 * 40) + 24
34103479 sta COLRAM + (15 * 40) + 25
3480+
3481+ ; Check if this was a new high score
3482+ lda new_high_score
3483+ beq res_show_prev_hs
3484+
3485+ ; Draw "NEW HIGH SCORE!" in bright cyan
3486+ ldx #0
3487+res_draw_new_hs:
3488+ lda new_hs_text,x
3489+ bne + ; Branch over jump if not zero
3490+ jmp res_draw_return ; Far jump when zero
3491++ sta SCREEN + (17 * 40) + 12,x
3492+ lda #3 ; Cyan
3493+ sta COLRAM + (17 * 40) + 12,x
3494+ inx
3495+ jmp res_draw_new_hs
3496+
3497+res_show_prev_hs:
3498+ ; Draw "HIGH SCORE:" label
3499+ ldx #0
3500+res_draw_hs_label:
3501+ lda high_score_text,x
3502+ beq res_draw_hs_value
3503+ sta SCREEN + (17 * 40) + 12,x
3504+ lda #11 ; Dark grey
3505+ sta COLRAM + (17 * 40) + 12,x
3506+ inx
3507+ jmp res_draw_hs_label
3508+
3509+res_draw_hs_value:
3510+ ; Get high score for current song/difficulty
3511+ jsr get_high_score
3512+
3513+ ; Display 5-digit high score
3514+ ldx #0
3515+res_hs_div_10000:
3516+ lda work_lo
3517+ sec
3518+ sbc #<10000
3519+ tay
3520+ lda work_hi
3521+ sbc #>10000
3522+ bcc res_hs_done_10000
3523+ sta work_hi
3524+ sty work_lo
3525+ inx
3526+ jmp res_hs_div_10000
3527+res_hs_done_10000:
3528+ txa
3529+ ora #$30
3530+ sta SCREEN + (17 * 40) + 24
3531+
3532+ ldx #0
3533+res_hs_div_1000:
3534+ lda work_lo
3535+ sec
3536+ sbc #<1000
3537+ tay
3538+ lda work_hi
3539+ sbc #>1000
3540+ bcc res_hs_done_1000
3541+ sta work_hi
3542+ sty work_lo
3543+ inx
3544+ jmp res_hs_div_1000
3545+res_hs_done_1000:
3546+ txa
3547+ ora #$30
3548+ sta SCREEN + (17 * 40) + 25
3549+
3550+ ldx #0
3551+res_hs_div_100:
3552+ lda work_lo
3553+ sec
3554+ sbc #100
3555+ bcc res_hs_done_100
3556+ sta work_lo
3557+ inx
3558+ jmp res_hs_div_100
3559+res_hs_done_100:
3560+ txa
3561+ ora #$30
3562+ sta SCREEN + (17 * 40) + 26
3563+
3564+ ldx #0
3565+res_hs_div_10:
3566+ lda work_lo
3567+ sec
3568+ sbc #10
3569+ bcc res_hs_done_10
3570+ sta work_lo
3571+ inx
3572+ jmp res_hs_div_10
3573+res_hs_done_10:
3574+ txa
3575+ ora #$30
3576+ sta SCREEN + (17 * 40) + 27
3577+
3578+ lda work_lo
3579+ ora #$30
3580+ sta SCREEN + (17 * 40) + 28
3581+
3582+ ; Colour high score digits
3583+ lda #11
3584+ sta COLRAM + (17 * 40) + 24
3585+ sta COLRAM + (17 * 40) + 25
3586+ sta COLRAM + (17 * 40) + 26
3587+ sta COLRAM + (17 * 40) + 27
3588+ sta COLRAM + (17 * 40) + 28
34113589
3590+res_draw_return:
34123591 ; Draw "PRESS FIRE"
34133592 ldx #0
34143593 draw_return:
...
34563635 ; ----------------------------------------------------------------------------
34573636
34583637 show_gameover:
3638+ ; Check if we beat the high score
3639+ jsr check_high_score
3640+
34593641 ; Clear screen
34603642 ldx #0
34613643 lda #CHAR_SPACE
...
35703752 sta COLRAM + (12 * 40) + 25
35713753 sta COLRAM + (12 * 40) + 26
35723754 sta COLRAM + (12 * 40) + 27
3755+
3756+ ; Check if this was a new high score
3757+ lda new_high_score
3758+ beq draw_prev_high
3759+
3760+ ; Draw "NEW HIGH SCORE!" in bright cyan
3761+ ldx #0
3762+draw_new_hs:
3763+ lda new_hs_text,x
3764+ bne + ; Branch over jump if not zero
3765+ jmp go_draw_retry ; Far jump when zero
3766++ sta SCREEN + (14 * 40) + 12,x
3767+ lda #3 ; Cyan
3768+ sta COLRAM + (14 * 40) + 12,x
3769+ inx
3770+ jmp draw_new_hs
3771+
3772+draw_prev_high:
3773+ ; Draw "HIGH SCORE:" label
3774+ ldx #0
3775+draw_hs_label:
3776+ lda high_score_text,x
3777+ beq draw_hs_value
3778+ sta SCREEN + (14 * 40) + 12,x
3779+ lda #11 ; Dark grey
3780+ sta COLRAM + (14 * 40) + 12,x
3781+ inx
3782+ jmp draw_hs_label
3783+
3784+draw_hs_value:
3785+ ; Get current high score into work_lo/work_hi
3786+ jsr get_high_score
3787+
3788+ ; Draw 5-digit high score value
3789+ ldx #0
3790+hs_div_10000:
3791+ lda work_lo
3792+ sec
3793+ sbc #<10000
3794+ tay
3795+ lda work_hi
3796+ sbc #>10000
3797+ bcc hs_done_10000
3798+ sta work_hi
3799+ sty work_lo
3800+ inx
3801+ jmp hs_div_10000
3802+hs_done_10000:
3803+ txa
3804+ ora #$30
3805+ sta SCREEN + (14 * 40) + 24
3806+
3807+ ldx #0
3808+hs_div_1000:
3809+ lda work_lo
3810+ sec
3811+ sbc #<1000
3812+ tay
3813+ lda work_hi
3814+ sbc #>1000
3815+ bcc hs_done_1000
3816+ sta work_hi
3817+ sty work_lo
3818+ inx
3819+ jmp hs_div_1000
3820+hs_done_1000:
3821+ txa
3822+ ora #$30
3823+ sta SCREEN + (14 * 40) + 25
3824+
3825+ ldx #0
3826+hs_div_100:
3827+ lda work_lo
3828+ sec
3829+ sbc #100
3830+ bcc hs_done_100
3831+ sta work_lo
3832+ inx
3833+ jmp hs_div_100
3834+hs_done_100:
3835+ txa
3836+ ora #$30
3837+ sta SCREEN + (14 * 40) + 26
3838+
3839+ ldx #0
3840+hs_div_10:
3841+ lda work_lo
3842+ sec
3843+ sbc #10
3844+ bcc hs_done_10
3845+ sta work_lo
3846+ inx
3847+ jmp hs_div_10
3848+hs_done_10:
3849+ txa
3850+ ora #$30
3851+ sta SCREEN + (14 * 40) + 27
3852+
3853+ lda work_lo
3854+ ora #$30
3855+ sta SCREEN + (14 * 40) + 28
3856+
3857+ ; Colour high score digits
3858+ lda #11
3859+ sta COLRAM + (14 * 40) + 24
3860+ sta COLRAM + (14 * 40) + 25
3861+ sta COLRAM + (14 * 40) + 26
3862+ sta COLRAM + (14 * 40) + 27
3863+ sta COLRAM + (14 * 40) + 28
35733864
3865+go_draw_retry:
35743866 ; Draw retry message
35753867 ldx #0
35763868 draw_retry:
...
35913883
35923884 gameover_score:
35933885 !scr "your score:"
3886+ !byte 0
3887+
3888+new_hs_text:
3889+ !scr "new high score!"
3890+ !byte 0
3891+
3892+high_score_text:
3893+ !scr "high score:"
35943894 !byte 0
35953895
35963896 retry_text:
...
41344434 health: !byte 0
41354435 combo: !byte 0
41364436 max_combo: !byte 0
4437+new_high_score: !byte 0 ; Flag: 1 if current score beat high score
4438+
4439+; ----------------------------------------------------------------------------
4440+; High Score Table (4 songs x 3 difficulties = 12 entries, 2 bytes each)
4441+; Index = (song * 3) + difficulty
4442+; ----------------------------------------------------------------------------
4443+
4444+high_scores:
4445+ ; Song 1 (First Steps)
4446+ !word 0 ; Easy high score
4447+ !word 0 ; Normal high score
4448+ !word 0 ; Hard high score
4449+ ; Song 2 (Upbeat Groove)
4450+ !word 0 ; Easy
4451+ !word 0 ; Normal
4452+ !word 0 ; Hard
4453+ ; Song 3 (Speed Rush)
4454+ !word 0 ; Easy
4455+ !word 0 ; Normal
4456+ !word 0 ; Hard
4457+ ; Song 4 (Off-Beat)
4458+ !word 0 ; Easy
4459+ !word 0 ; Normal
4460+ !word 0 ; Hard
41374461
41384462 ; ============================================================================
4139-; END OF SID SYMPHONY - UNIT 19
4463+; END OF SID SYMPHONY - UNIT 25
41404464 ; ============================================================================
41414465