Game 1 Unit 13 of 64 1 hr learning time
Title Screen
A proper title screen. Press fire to start. Complete game flow.
20% of SID Symphony
First impressions matter. This unit adds a proper title screen.
The game now starts with “SID SYMPHONY” displayed prominently on a clean black screen. “PRESS FIRE TO START” prompts the player. After completing a song or failing, pressing fire returns to the title. The complete game loop is now in place: Title → Playing → Results → Title.
Run It
Assemble and run:
acme -f cbm -o symphony.prg symphony.asm
Press fire on a joystick (port 2) or space on the keyboard to start. Play through the song, see your results, then fire returns you to the title.
Four Game States
The game now has four distinct states:
; ============================================================================
; GAME STATES - Four distinct states for complete game flow
; ============================================================================
STATE_TITLE = 0 ; Title screen - waiting to start
STATE_PLAYING = 1 ; Main gameplay
STATE_RESULTS = 2 ; Song completed successfully
STATE_GAMEOVER = 3 ; Health depleted - game over
game_state: !byte 0 ; Current state
; ----------------------------------------------------------------------------
; Main Loop - State Dispatcher
; ----------------------------------------------------------------------------
main_loop:
lda #$FF
wait_raster:
cmp $D012
bne wait_raster
lda game_state
cmp #STATE_TITLE
beq do_title
cmp #STATE_PLAYING
beq do_playing
cmp #STATE_RESULTS
beq do_results
jmp do_gameover
do_title:
jsr update_title
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
Each frame, the main loop checks game_state and calls the appropriate update routine. This pattern - a variable controlling which code runs - scales to any number of states.
The State Machine Pattern
The state machine is one of the most useful patterns in game development:
┌───────────┐ fire ┌──────────┐
│ TITLE │ ────────────────▶│ PLAYING │
└───────────┘ └──────────┘
▲ │
│ │
fire song ends / health = 0
│ │
│ ▼
┌───────────┐ ┌──────────┐
│ RESULTS │◀────────────────│ GAMEOVER │
└───────────┘ song complete └──────────┘Each state handles its own logic and decides when to transition to another state.
The Title Screen
The title screen displays the game name and instructions:
; ----------------------------------------------------------------------------
; 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 game title
ldx #0
draw_title_text:
lda title_big,x
beq draw_title_done
sta SCREEN + (8 * 40) + 14,x ; Row 8, centered
lda #TITLE_COL ; White
sta COLRAM + (8 * 40) + 14,x
inx
jmp draw_title_text
draw_title_done:
; Draw subtitle
ldx #0
draw_subtitle:
lda subtitle_text,x
beq draw_subtitle_done
sta SCREEN + (10 * 40) + 13,x ; Row 10
lda #SUBTITLE_COL ; Grey
sta COLRAM + (10 * 40) + 13,x
inx
jmp draw_subtitle
draw_subtitle_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 ; Row 20
lda #7 ; Yellow - draws attention
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
press_fire_text:
!scr "press fire to start"
!byte 0
Three elements: the title in white (draws the eye), subtitle in grey (provides context), and “PRESS FIRE TO START” in yellow (calls to action).
Waiting for Fire
The title state waits for the fire button:
; ----------------------------------------------------------------------------
; Update Title State - Wait for fire button to start
; ----------------------------------------------------------------------------
update_title:
; Check joystick port 2 fire button
lda CIA1_PRA
and #$10 ; Bit 4 = fire button
beq fire_pressed ; Low = pressed
; Also accept space bar as alternative
lda #$7F ; Select keyboard row 7
sta CIA1_PRA
lda CIA1_PRB
and #$10 ; Space bar
beq fire_pressed
; No input - stay on title screen
lda #$FF
sta CIA1_PRA ; Reset CIA
rts
fire_pressed:
lda #$FF
sta CIA1_PRA ; Reset CIA
; Start the game!
jsr init_game ; Initialize all game systems
lda #STATE_PLAYING
sta game_state ; Transition to playing state
rts
; ----------------------------------------------------------------------------
; Update Results - Return to title on fire
; ----------------------------------------------------------------------------
update_results:
lda CIA1_PRA
and #$10
beq results_fire
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
; Return to title - complete game loop
jsr show_title
lda #STATE_TITLE
sta game_state
rts
We check both joystick port 2 (bit 4 of CIA1_PRA) and space bar as alternatives. When fire is detected, we initialise the game and transition to PLAYING state.
Returning to Title
After results or game over, pressing fire returns to the title instead of restarting immediately:
update_results:
; Check for fire
lda CIA1_PRA
and #$10
beq results_fire
; ... space bar check ...
rts
results_fire:
jsr show_title ; Draw title screen
lda #STATE_TITLE
sta game_state ; Return to title
rtsThis creates a proper game loop. Players see the title between every play session.
Clean Initialisation
When transitioning from title to playing, init_game resets everything:
init_game:
jsr init_screen ; Clear and draw tracks
jsr init_notes ; Clear note arrays
jsr init_score ; Reset score to 0
jsr init_health ; Reset health to starting value
jsr init_combo ; Reset combo to 0
jsr init_song ; Reset song position
rtsEach play session starts fresh. Previous scores, health, or combos don’t carry over.
The Complete Code
; ============================================================================
; SID SYMPHONY - Unit 13: Title Screen
; ============================================================================
; The game now starts with a proper title screen. Press fire to play.
; Complete game flow: Title -> Playing -> Results -> Title.
;
; Controls: Z = Track 1 (high), X = Track 2 (mid), C = Track 3 (low)
; Fire = Start game from title screen
; ============================================================================
; ============================================================================
; CUSTOMISATION SECTION
; ============================================================================
; SID Voice Settings
VOICE1_WAVE = $21
VOICE2_WAVE = $41
VOICE3_WAVE = $11
VOICE1_FREQ = $1C
VOICE2_FREQ = $0E
VOICE3_FREQ = $07
VOICE_AD = $09
VOICE_SR = $00
PULSE_WIDTH = $08
; Miss sound settings
MISS_FREQ = $08
MISS_WAVE = $81
MISS_AD = $00
MISS_SR = $90
; Visual Settings
BORDER_COL = 0
BG_COL = 0
TRACK1_NOTE_COL = 10
TRACK2_NOTE_COL = 13
TRACK3_NOTE_COL = 14
TRACK_LINE_COL = 11
HIT_ZONE_COL = 7
HIT_COL = 1
PERFECT_COL = 1
GOOD_COL = 7
MISS_COL = 2
HEALTH_COL = 5
PROGRESS_COL = 3
COMBO_COL = 13
; Title screen colours
TITLE_COL = 1 ; White for title
SUBTITLE_COL = 11 ; Grey for subtitle
; ============================================================================
; SCORING SETTINGS
; ============================================================================
PERFECT_SCORE = 100
GOOD_SCORE = 50
; ============================================================================
; COMBO SETTINGS
; ============================================================================
COMBO_TIER_2 = 10
COMBO_TIER_3 = 25
COMBO_TIER_4 = 50
; ============================================================================
; HEALTH SETTINGS
; ============================================================================
HEALTH_MAX = 64
HEALTH_START = 32
HEALTH_PERFECT = 4
HEALTH_GOOD = 2
HEALTH_MISS = 8
; ============================================================================
; HIT DETECTION SETTINGS
; ============================================================================
HIT_ZONE_MIN = 2
HIT_ZONE_MAX = 5
HIT_ZONE_CENTRE = 3
; ============================================================================
; SONG SETTINGS
; ============================================================================
SONG_LENGTH = 64
PROGRESS_WIDTH = 16
; ============================================================================
; GAME STATES
; ============================================================================
STATE_TITLE = 0 ; NEW: Title screen
STATE_PLAYING = 1
STATE_RESULTS = 2
STATE_GAMEOVER = 3
; ============================================================================
; 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
TRACK1_ROW = 8
TRACK2_ROW = 12
TRACK3_ROW = 16
; HUD positions
HEALTH_ROW = 23
PROGRESS_ROW = 24
; Combo display position
COMBO_ROW = 2
; Hit zone
HIT_ZONE_COLUMN = 3
; Custom character codes
CHAR_NOTE = 128
CHAR_TRACK = 129
CHAR_HITZONE = 130
CHAR_SPACE = 32
CHAR_BAR_FULL = 131
CHAR_BAR_EMPTY = 132
; Note settings
MAX_NOTES = 8
NOTE_SPAWN_COL = 37
; Timing
FRAMES_PER_BEAT = 25
END_DELAY_FRAMES = 75
; 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
; ----------------------------------------------------------------------------
; BASIC Stub
; ----------------------------------------------------------------------------
* = $0801
!byte $0C, $08
!byte $0A, $00
!byte $9E
!text "2064"
!byte $00
!byte $00, $00
; ----------------------------------------------------------------------------
; Main Program
; ----------------------------------------------------------------------------
* = $0810
start:
jsr copy_charset
jsr init_sid
jsr show_title
; Start in TITLE state
lda #STATE_TITLE
sta game_state
main_loop:
lda #$FF
wait_raster:
cmp $D012
bne wait_raster
lda game_state
cmp #STATE_TITLE
beq do_title
cmp #STATE_PLAYING
beq do_playing
cmp #STATE_RESULTS
beq do_results
jmp do_gameover
do_title:
jsr update_title
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 fire_pressed
; Also check space bar as alternative
lda #$7F
sta CIA1_PRA
lda CIA1_PRB
and #$10 ; Space
beq fire_pressed
; No input - stay on title
lda #$FF
sta CIA1_PRA
rts
fire_pressed:
lda #$FF
sta CIA1_PRA
; Start the game!
jsr init_game
lda #STATE_PLAYING
sta game_state
rts
; ----------------------------------------------------------------------------
; Initialize Game (called when starting from title)
; ----------------------------------------------------------------------------
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 title
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
; Return to title screen
jsr show_title
lda #STATE_TITLE
sta game_state
rts
; ----------------------------------------------------------------------------
; Update Game Over State
; ----------------------------------------------------------------------------
update_gameover:
; Check for fire to return to title
lda CIA1_PRA
and #$10
beq gameover_fire
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
; Return to title screen
jsr show_title
lda #STATE_TITLE
sta game_state
rts
; ----------------------------------------------------------------------------
; Check Song End
; ----------------------------------------------------------------------------
check_song_end:
lda song_ended
beq song_not_ended
ldx #0
check_notes_clear:
lda note_track,x
bne notes_still_active
inx
cpx #MAX_NOTES
bne check_notes_clear
dec end_delay
bne song_not_ended
jsr show_results
lda #STATE_RESULTS
sta game_state
notes_still_active:
song_not_ended:
rts
; ----------------------------------------------------------------------------
; Initialize Song
; ----------------------------------------------------------------------------
init_song:
lda #<song_data
sta song_pos
lda #>song_data
sta song_pos_hi
lda #0
sta frame_count
sta beat_count
sta song_beat
sta border_flash
sta song_ended
lda #END_DELAY_FRAMES
sta end_delay
jsr display_progress
rts
; ----------------------------------------------------------------------------
; Advance Song
; ----------------------------------------------------------------------------
advance_song:
lda song_ended
bne advance_done
inc beat_count
inc song_beat
lda song_beat
cmp #SONG_LENGTH
bcc song_continues
lda #1
sta song_ended
song_continues:
jsr display_progress
advance_done:
rts
; ----------------------------------------------------------------------------
; Display Progress
; ----------------------------------------------------------------------------
display_progress:
lda song_beat
lsr
lsr
sta temp_progress
ldx #0
lda temp_progress
beq draw_empty_progress
draw_full_progress:
lda #CHAR_BAR_FULL
sta SCREEN + (PROGRESS_ROW * 40) + 12,x
lda #PROGRESS_COL
sta COLRAM + (PROGRESS_ROW * 40) + 12,x
inx
cpx temp_progress
bne draw_full_progress
draw_empty_progress:
cpx #PROGRESS_WIDTH
beq progress_done
lda #CHAR_BAR_EMPTY
sta SCREEN + (PROGRESS_ROW * 40) + 12,x
lda #11
sta COLRAM + (PROGRESS_ROW * 40) + 12,x
inx
jmp draw_empty_progress
progress_done:
rts
temp_progress: !byte 0
; ----------------------------------------------------------------------------
; Get Multiplier
; ----------------------------------------------------------------------------
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
; ----------------------------------------------------------------------------
; Display Combo
; ----------------------------------------------------------------------------
display_combo:
ldx #0
draw_combo_label:
lda combo_label,x
beq draw_combo_value
sta SCREEN + (COMBO_ROW * 40) + 12,x
lda #11
sta COLRAM + (COMBO_ROW * 40) + 12,x
inx
jmp draw_combo_label
draw_combo_value:
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) + 18
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) + 19
pla
ora #$30
sta SCREEN + (COMBO_ROW * 40) + 20
jsr get_multiplier
cmp #4
beq combo_col_4x
cmp #3
beq combo_col_3x
cmp #2
beq combo_col_2x
lda #11
jmp set_combo_col
combo_col_2x:
lda #7
jmp set_combo_col
combo_col_3x:
lda #5
jmp set_combo_col
combo_col_4x:
lda #1
set_combo_col:
sta COLRAM + (COMBO_ROW * 40) + 18
sta COLRAM + (COMBO_ROW * 40) + 19
sta COLRAM + (COMBO_ROW * 40) + 20
jsr get_multiplier
ora #$30
sta SCREEN + (COMBO_ROW * 40) + 22
lda #$18
sta SCREEN + (COMBO_ROW * 40) + 23
jsr get_multiplier
cmp #4
beq mult_col_4x
cmp #3
beq mult_col_3x
cmp #2
beq mult_col_2x
lda #11
jmp set_mult_col
mult_col_2x:
lda #7
jmp set_mult_col
mult_col_3x:
lda #5
jmp set_mult_col
mult_col_4x:
lda #1
set_mult_col:
sta COLRAM + (COMBO_ROW * 40) + 22
sta COLRAM + (COMBO_ROW * 40) + 23
rts
combo_label:
!scr "combo:"
!byte 0
; ----------------------------------------------------------------------------
; Increment Combo
; ----------------------------------------------------------------------------
increment_combo:
inc combo
lda combo
cmp max_combo
bcc combo_not_max
sta max_combo
combo_not_max:
jsr display_combo
rts
; ----------------------------------------------------------------------------
; Break Combo
; ----------------------------------------------------------------------------
break_combo:
lda combo
beq combo_already_zero
lda #0
sta combo
jsr display_combo
combo_already_zero:
rts
; ----------------------------------------------------------------------------
; Show Results Screen
; ----------------------------------------------------------------------------
show_results:
ldx #0
lda #CHAR_SPACE
clear_for_results:
sta SCREEN,x
sta SCREEN+$100,x
sta SCREEN+$200,x
sta SCREEN+$2E8,x
inx
bne clear_for_results
ldx #0
draw_results_title:
lda results_title,x
beq draw_results_title_done
sta SCREEN + (3 * 40) + 14,x
lda #1
sta COLRAM + (3 * 40) + 14,x
inx
jmp draw_results_title
draw_results_title_done:
ldx #0
draw_final_score_label:
lda final_score_label,x
beq draw_final_score_done
sta SCREEN + (6 * 40) + 10,x
lda #7
sta COLRAM + (6 * 40) + 10,x
inx
jmp draw_final_score_label
draw_final_score_done:
jsr display_final_score
ldx #0
draw_perfects_label:
lda perfects_label,x
beq draw_perfects_done
sta SCREEN + (8 * 40) + 10,x
lda #1
sta COLRAM + (8 * 40) + 10,x
inx
jmp draw_perfects_label
draw_perfects_done:
lda perfect_count
jsr display_stat_at_8
ldx #0
draw_goods_label:
lda goods_label,x
beq draw_goods_done
sta SCREEN + (9 * 40) + 10,x
lda #7
sta COLRAM + (9 * 40) + 10,x
inx
jmp draw_goods_label
draw_goods_done:
lda good_count
jsr display_stat_at_9
ldx #0
draw_misses_label:
lda misses_label,x
beq draw_misses_done
sta SCREEN + (10 * 40) + 10,x
lda #2
sta COLRAM + (10 * 40) + 10,x
inx
jmp draw_misses_label
draw_misses_done:
lda miss_count
jsr display_stat_at_10
ldx #0
draw_max_combo_label:
lda max_combo_label,x
beq draw_max_combo_done
sta SCREEN + (12 * 40) + 10,x
lda #13
sta COLRAM + (12 * 40) + 10,x
inx
jmp draw_max_combo_label
draw_max_combo_done:
lda max_combo
jsr display_stat_at_12
ldx #0
draw_accuracy_label:
lda accuracy_label,x
beq draw_accuracy_done
sta SCREEN + (14 * 40) + 10,x
lda #5
sta COLRAM + (14 * 40) + 10,x
inx
jmp draw_accuracy_label
draw_accuracy_done:
jsr calculate_accuracy
jsr display_accuracy
ldx #0
draw_press_key:
lda press_fire_results,x
beq draw_press_key_done
sta SCREEN + (18 * 40) + 9,x
lda #7
sta COLRAM + (18 * 40) + 9,x
inx
jmp draw_press_key
draw_press_key_done:
lda #5
sta BORDER
rts
results_title:
!scr "song complete!"
!byte 0
final_score_label:
!scr "final score:"
!byte 0
perfects_label:
!scr "perfects:"
!byte 0
goods_label:
!scr "goods:"
!byte 0
misses_label:
!scr "misses:"
!byte 0
max_combo_label:
!scr "max combo:"
!byte 0
accuracy_label:
!scr "accuracy:"
!byte 0
press_fire_results:
!scr "press fire for title"
!byte 0
; ----------------------------------------------------------------------------
; Display Final Score
; ----------------------------------------------------------------------------
display_final_score:
lda score_lo
sta work_lo
lda score_hi
sta work_hi
ldx #0
fs_div_10000:
lda work_lo
sec
sbc #<10000
tay
lda work_hi
sbc #>10000
bcc fs_done_10000
sta work_hi
sty work_lo
inx
jmp fs_div_10000
fs_done_10000:
txa
ora #$30
sta SCREEN + (6 * 40) + 23
ldx #0
fs_div_1000:
lda work_lo
sec
sbc #<1000
tay
lda work_hi
sbc #>1000
bcc fs_done_1000
sta work_hi
sty work_lo
inx
jmp fs_div_1000
fs_done_1000:
txa
ora #$30
sta SCREEN + (6 * 40) + 24
ldx #0
fs_div_100:
lda work_lo
sec
sbc #100
bcc fs_done_100
sta work_lo
inx
jmp fs_div_100
fs_done_100:
txa
ora #$30
sta SCREEN + (6 * 40) + 25
ldx #0
fs_div_10:
lda work_lo
sec
sbc #10
bcc fs_done_10
sta work_lo
inx
jmp fs_div_10
fs_done_10:
txa
ora #$30
sta SCREEN + (6 * 40) + 26
lda work_lo
ora #$30
sta SCREEN + (6 * 40) + 27
lda #7
sta COLRAM + (6 * 40) + 23
sta COLRAM + (6 * 40) + 24
sta COLRAM + (6 * 40) + 25
sta COLRAM + (6 * 40) + 26
sta COLRAM + (6 * 40) + 27
rts
; ----------------------------------------------------------------------------
; Display Stats
; ----------------------------------------------------------------------------
display_stat_at_8:
ldx #0
stat8_div:
cmp #10
bcc stat8_done
sec
sbc #10
inx
jmp stat8_div
stat8_done:
pha
txa
ora #$30
sta SCREEN + (8 * 40) + 23
pla
ora #$30
sta SCREEN + (8 * 40) + 24
lda #1
sta COLRAM + (8 * 40) + 23
sta COLRAM + (8 * 40) + 24
rts
display_stat_at_9:
ldx #0
stat9_div:
cmp #10
bcc stat9_done
sec
sbc #10
inx
jmp stat9_div
stat9_done:
pha
txa
ora #$30
sta SCREEN + (9 * 40) + 23
pla
ora #$30
sta SCREEN + (9 * 40) + 24
lda #7
sta COLRAM + (9 * 40) + 23
sta COLRAM + (9 * 40) + 24
rts
display_stat_at_10:
ldx #0
stat10_div:
cmp #10
bcc stat10_done
sec
sbc #10
inx
jmp stat10_div
stat10_done:
pha
txa
ora #$30
sta SCREEN + (10 * 40) + 23
pla
ora #$30
sta SCREEN + (10 * 40) + 24
lda #2
sta COLRAM + (10 * 40) + 23
sta COLRAM + (10 * 40) + 24
rts
display_stat_at_12:
ldx #0
stat12_div:
cmp #10
bcc stat12_done
sec
sbc #10
inx
jmp stat12_div
stat12_done:
pha
txa
ora #$30
sta SCREEN + (12 * 40) + 23
pla
ora #$30
sta SCREEN + (12 * 40) + 24
lda #13
sta COLRAM + (12 * 40) + 23
sta COLRAM + (12 * 40) + 24
rts
; ----------------------------------------------------------------------------
; Calculate Accuracy
; ----------------------------------------------------------------------------
calculate_accuracy:
lda perfect_count
clc
adc good_count
sta total_hits
clc
adc miss_count
sta total_notes
beq accuracy_zero
lda total_hits
sta dividend_lo
lda #0
sta dividend_hi
ldx #100
mult_loop:
dex
beq mult_done
lda dividend_lo
clc
adc total_hits
sta dividend_lo
lda dividend_hi
adc #0
sta dividend_hi
jmp mult_loop
mult_done:
lda #0
sta accuracy
div_loop:
lda dividend_lo
sec
sbc total_notes
tay
lda dividend_hi
sbc #0
bcc div_done
sta dividend_hi
sty dividend_lo
inc accuracy
jmp div_loop
div_done:
rts
accuracy_zero:
lda #0
sta accuracy
rts
total_hits: !byte 0
total_notes: !byte 0
dividend_lo: !byte 0
dividend_hi: !byte 0
accuracy: !byte 0
; ----------------------------------------------------------------------------
; Display Accuracy
; ----------------------------------------------------------------------------
display_accuracy:
lda accuracy
ldx #0
acc_div_100:
cmp #100
bcc acc_done_100
sec
sbc #100
inx
jmp acc_div_100
acc_done_100:
pha
txa
ora #$30
sta SCREEN + (14 * 40) + 23
pla
ldx #0
acc_div_10:
cmp #10
bcc acc_done_10
sec
sbc #10
inx
jmp acc_div_10
acc_done_10:
pha
txa
ora #$30
sta SCREEN + (14 * 40) + 24
pla
ora #$30
sta SCREEN + (14 * 40) + 25
lda #$25
sta SCREEN + (14 * 40) + 26
lda #5
sta COLRAM + (14 * 40) + 23
sta COLRAM + (14 * 40) + 24
sta COLRAM + (14 * 40) + 25
sta COLRAM + (14 * 40) + 26
rts
; ----------------------------------------------------------------------------
; Copy Character Set
; ----------------------------------------------------------------------------
copy_charset:
sei
lda $01
pha
and #$FB
sta $01
ldx #0
copy_loop:
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_loop
pla
sta $01
cli
jsr define_custom_chars
lda #$1C
sta CHARPTR
rts
; ----------------------------------------------------------------------------
; Define Custom Characters
; ----------------------------------------------------------------------------
define_custom_chars:
lda #%00000110
sta CHARSET + (CHAR_NOTE * 8) + 0
lda #%00011110
sta CHARSET + (CHAR_NOTE * 8) + 1
lda #%01111110
sta CHARSET + (CHAR_NOTE * 8) + 2
lda #%11111110
sta CHARSET + (CHAR_NOTE * 8) + 3
lda #%11111110
sta CHARSET + (CHAR_NOTE * 8) + 4
lda #%01111110
sta CHARSET + (CHAR_NOTE * 8) + 5
lda #%00011110
sta CHARSET + (CHAR_NOTE * 8) + 6
lda #%00000110
sta CHARSET + (CHAR_NOTE * 8) + 7
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 0
sta CHARSET + (CHAR_TRACK * 8) + 1
sta CHARSET + (CHAR_TRACK * 8) + 2
lda #%11111111
sta CHARSET + (CHAR_TRACK * 8) + 3
sta CHARSET + (CHAR_TRACK * 8) + 4
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 5
sta CHARSET + (CHAR_TRACK * 8) + 6
sta CHARSET + (CHAR_TRACK * 8) + 7
lda #%01100110
sta CHARSET + (CHAR_HITZONE * 8) + 0
sta CHARSET + (CHAR_HITZONE * 8) + 1
sta CHARSET + (CHAR_HITZONE * 8) + 2
sta CHARSET + (CHAR_HITZONE * 8) + 3
sta CHARSET + (CHAR_HITZONE * 8) + 4
sta CHARSET + (CHAR_HITZONE * 8) + 5
sta CHARSET + (CHAR_HITZONE * 8) + 6
sta CHARSET + (CHAR_HITZONE * 8) + 7
lda #%11111111
sta CHARSET + (CHAR_BAR_FULL * 8) + 0
sta CHARSET + (CHAR_BAR_FULL * 8) + 1
sta CHARSET + (CHAR_BAR_FULL * 8) + 2
sta CHARSET + (CHAR_BAR_FULL * 8) + 3
sta CHARSET + (CHAR_BAR_FULL * 8) + 4
sta CHARSET + (CHAR_BAR_FULL * 8) + 5
sta CHARSET + (CHAR_BAR_FULL * 8) + 6
sta CHARSET + (CHAR_BAR_FULL * 8) + 7
lda #%11111111
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 0
lda #%10000001
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 1
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 2
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 3
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 4
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 5
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 6
lda #%11111111
sta CHARSET + (CHAR_BAR_EMPTY * 8) + 7
rts
; ----------------------------------------------------------------------------
; Initialize Health
; ----------------------------------------------------------------------------
init_health:
lda #HEALTH_START
sta health
jsr display_health
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 Notes
; ----------------------------------------------------------------------------
init_notes:
ldx #MAX_NOTES-1
lda #0
init_notes_loop:
sta note_track,x
sta note_col,x
sta note_freq,x
dex
bpl init_notes_loop
rts
; ----------------------------------------------------------------------------
; Check Spawn Note
; ----------------------------------------------------------------------------
check_spawn_note:
lda song_ended
bne spawn_done_early
ldy #0
spawn_check_loop:
lda (song_pos),y
cmp #$FF
beq spawn_song_end
cmp beat_count
beq spawn_match
bcs spawn_done_early
jmp spawn_advance
spawn_match:
iny
lda (song_pos),y
sta temp_track
iny
lda (song_pos),y
pha
lda temp_track
jsr spawn_note_with_freq
pla
dey
dey
spawn_advance:
lda song_pos
clc
adc #3
sta song_pos
lda song_pos_hi
adc #0
sta song_pos_hi
jmp spawn_check_loop
spawn_song_end:
lda #1
sta song_ended
spawn_done_early:
rts
; ----------------------------------------------------------------------------
; Spawn Note With Frequency
; ----------------------------------------------------------------------------
spawn_note_with_freq:
sta temp_track
ldx #0
spawn_find_slot:
lda note_track,x
beq spawn_found_slot
inx
cpx #MAX_NOTES
bne spawn_find_slot
rts
spawn_found_slot:
lda temp_track
sta note_track,x
lda #NOTE_SPAWN_COL
sta note_col,x
tsx
lda $0103,x
sta note_freq,x
jsr draw_note
rts
; ----------------------------------------------------------------------------
; Update Notes
; ----------------------------------------------------------------------------
update_notes:
ldx #0
update_loop:
lda note_track,x
beq update_next
jsr erase_note
dec note_col,x
lda note_col,x
cmp #1
bcc update_miss
jsr draw_note
jmp update_next
update_miss:
lda note_track,x
sta miss_track
lda #0
sta note_track,x
jsr handle_miss
update_next:
inx
cpx #MAX_NOTES
bne update_loop
rts
; ----------------------------------------------------------------------------
; Handle Miss
; ----------------------------------------------------------------------------
handle_miss:
inc miss_count
jsr play_miss_sound
lda #MISS_COL
sta BORDER
lda #8
sta border_flash
jsr display_misses
jsr decrease_health
jsr break_combo
rts
; ----------------------------------------------------------------------------
; Decrease Health
; ----------------------------------------------------------------------------
decrease_health:
lda health
sec
sbc #HEALTH_MISS
bcc health_zero
sta health
jsr display_health
jsr check_game_over
rts
health_zero:
lda #0
sta health
jsr display_health
jsr check_game_over
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
; ----------------------------------------------------------------------------
; Check Game Over
; ----------------------------------------------------------------------------
check_game_over:
lda health
bne not_game_over
lda #STATE_GAMEOVER
sta game_state
jsr show_game_over
not_game_over:
rts
; ----------------------------------------------------------------------------
; Show Game Over
; ----------------------------------------------------------------------------
show_game_over:
ldx #0
game_over_loop:
lda game_over_text,x
beq game_over_text_done
sta SCREEN + (10 * 40) + 15,x
lda #2
sta COLRAM + (10 * 40) + 15,x
inx
jmp game_over_loop
game_over_text_done:
ldx #0
game_over_press:
lda press_fire_gameover,x
beq game_over_done
sta SCREEN + (14 * 40) + 9,x
lda #7
sta COLRAM + (14 * 40) + 9,x
inx
jmp game_over_press
game_over_done:
lda #2
sta BORDER
rts
game_over_text:
!scr "game over"
!byte 0
press_fire_gameover:
!scr "press fire for title"
!byte 0
; ----------------------------------------------------------------------------
; Display Health
; ----------------------------------------------------------------------------
display_health:
lda health
lsr
lsr
lsr
sta temp_health
ldx #0
lda temp_health
beq draw_empty_bars
draw_full_bars:
lda #CHAR_BAR_FULL
sta SCREEN + (HEALTH_ROW * 40) + 12,x
lda #HEALTH_COL
sta COLRAM + (HEALTH_ROW * 40) + 12,x
inx
cpx temp_health
bne draw_full_bars
draw_empty_bars:
cpx #8
beq health_done
lda #CHAR_BAR_EMPTY
sta SCREEN + (HEALTH_ROW * 40) + 12,x
lda #11
sta COLRAM + (HEALTH_ROW * 40) + 12,x
inx
jmp draw_empty_bars
health_done:
rts
temp_health: !byte 0
; ----------------------------------------------------------------------------
; Play Miss Sound
; ----------------------------------------------------------------------------
play_miss_sound:
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
; ----------------------------------------------------------------------------
; Draw Note
; ----------------------------------------------------------------------------
draw_note:
lda note_track,x
cmp #1
beq draw_note_t1
cmp #2
beq draw_note_t2
cmp #3
beq draw_note_t3
rts
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
ldy #0
lda #CHAR_NOTE
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 #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
ldy #0
lda #CHAR_NOTE
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
ldy #0
lda #CHAR_NOTE
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
cmp #3
beq erase_note_t3
rts
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
ldy #0
lda #CHAR_TRACK
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
ldy #0
lda #CHAR_TRACK
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
ldy #0
lda #CHAR_TRACK
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
; ----------------------------------------------------------------------------
; Initialize Screen
; ----------------------------------------------------------------------------
init_screen:
lda #BORDER_COL
sta BORDER
lda #BG_COL
sta BGCOL
ldx #0
lda #CHAR_SPACE
clr_screen:
sta SCREEN,x
sta SCREEN+$100,x
sta SCREEN+$200,x
sta SCREEN+$2E8,x
inx
bne clr_screen
ldx #0
lda #TRACK_LINE_COL
clr_colour:
sta COLRAM,x
sta COLRAM+$100,x
sta COLRAM+$200,x
sta COLRAM+$2E8,x
inx
bne clr_colour
jsr draw_tracks
jsr draw_hit_zones
jsr draw_labels
rts
; ----------------------------------------------------------------------------
; Draw Tracks
; ----------------------------------------------------------------------------
draw_tracks:
lda #CHAR_TRACK
ldx #0
draw_t1:
sta SCREEN + (TRACK1_ROW * 40),x
inx
cpx #38
bne draw_t1
ldx #0
draw_t2:
sta SCREEN + (TRACK2_ROW * 40),x
inx
cpx #38
bne draw_t2
ldx #0
draw_t3:
sta SCREEN + (TRACK3_ROW * 40),x
inx
cpx #38
bne draw_t3
rts
; ----------------------------------------------------------------------------
; Draw Hit Zones
; ----------------------------------------------------------------------------
draw_hit_zones:
lda #CHAR_HITZONE
sta SCREEN + ((TRACK1_ROW-2) * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK1_ROW-1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK1_ROW+1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK2_ROW-1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK2_ROW+1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK3_ROW-1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK3_ROW+1) * 40) + HIT_ZONE_COLUMN
sta SCREEN + ((TRACK3_ROW+2) * 40) + HIT_ZONE_COLUMN
lda #HIT_ZONE_COL
sta COLRAM + ((TRACK1_ROW-2) * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK1_ROW-1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK1_ROW+1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK2_ROW-1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK2_ROW+1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK3_ROW-1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK3_ROW+1) * 40) + HIT_ZONE_COLUMN
sta COLRAM + ((TRACK3_ROW+2) * 40) + HIT_ZONE_COLUMN
rts
; ----------------------------------------------------------------------------
; Draw Labels
; ----------------------------------------------------------------------------
draw_labels:
ldx #0
draw_score_label:
lda score_label,x
beq draw_score_label_done
sta SCREEN + 1,x
lda #1
sta COLRAM + 1,x
inx
bne draw_score_label
draw_score_label_done:
ldx #0
draw_miss_label:
lda miss_label,x
beq draw_miss_label_done
sta SCREEN + 15,x
lda #2
sta COLRAM + 15,x
inx
bne draw_miss_label
draw_miss_label_done:
ldx #0
draw_title_game:
lda title_game,x
beq draw_title_game_done
sta SCREEN + 27,x
lda #1
sta COLRAM + 27,x
inx
bne draw_title_game
draw_title_game_done:
ldx #0
draw_health_label:
lda health_label,x
beq draw_health_label_done
sta SCREEN + (HEALTH_ROW * 40) + 4,x
lda #5
sta COLRAM + (HEALTH_ROW * 40) + 4,x
inx
bne draw_health_label
draw_health_label_done:
ldx #0
draw_progress_label:
lda progress_label,x
beq draw_progress_label_done
sta SCREEN + (PROGRESS_ROW * 40) + 4,x
lda #3
sta COLRAM + (PROGRESS_ROW * 40) + 4,x
inx
bne draw_progress_label
draw_progress_label_done:
lda #$1A
sta SCREEN + (TRACK1_ROW * 40)
lda #TRACK1_NOTE_COL
sta COLRAM + (TRACK1_ROW * 40)
lda #$18
sta SCREEN + (TRACK2_ROW * 40)
lda #TRACK2_NOTE_COL
sta COLRAM + (TRACK2_ROW * 40)
lda #$03
sta SCREEN + (TRACK3_ROW * 40)
lda #TRACK3_NOTE_COL
sta COLRAM + (TRACK3_ROW * 40)
rts
score_label:
!scr "score:"
!byte 0
miss_label:
!scr "miss:"
!byte 0
title_game:
!scr "sid symphony"
!byte 0
health_label:
!scr "health:"
!byte 0
progress_label:
!scr "song:"
!byte 0
; ----------------------------------------------------------------------------
; Initialize SID
; ----------------------------------------------------------------------------
init_sid:
ldx #$18
lda #0
clear_sid:
sta SID,x
dex
bpl clear_sid
lda #$0F
sta SID_VOLUME
lda #$00
sta SID_V1_FREQ_LO
lda #VOICE1_FREQ
sta SID_V1_FREQ_HI
lda #PULSE_WIDTH
sta SID_V1_PWHI
lda #VOICE_AD
sta SID_V1_AD
lda #VOICE_SR
sta SID_V1_SR
lda #$00
sta SID_V2_FREQ_LO
lda #VOICE2_FREQ
sta SID_V2_FREQ_HI
lda #PULSE_WIDTH
sta SID_V2_PWHI
lda #VOICE_AD
sta SID_V2_AD
lda #VOICE_SR
sta SID_V2_SR
lda #$00
sta SID_V3_FREQ_LO
lda #VOICE3_FREQ
sta SID_V3_FREQ_HI
lda #PULSE_WIDTH
sta SID_V3_PWHI
lda #VOICE_AD
sta SID_V3_AD
lda #VOICE_SR
sta SID_V3_SR
rts
; ----------------------------------------------------------------------------
; Reset Track Colours
; ----------------------------------------------------------------------------
reset_track_colours:
ldx #0
lda #TRACK_LINE_COL
reset_t1:
sta COLRAM + (TRACK1_ROW * 40),x
inx
cpx #38
bne reset_t1
ldx #0
reset_t2:
sta COLRAM + (TRACK2_ROW * 40),x
inx
cpx #38
bne reset_t2
ldx #0
reset_t3:
sta COLRAM + (TRACK3_ROW * 40),x
inx
cpx #38
bne reset_t3
lda #TRACK1_NOTE_COL
sta COLRAM + (TRACK1_ROW * 40)
lda #TRACK2_NOTE_COL
sta COLRAM + (TRACK2_ROW * 40)
lda #TRACK3_NOTE_COL
sta COLRAM + (TRACK3_ROW * 40)
lda #HIT_ZONE_COL
sta COLRAM + (TRACK1_ROW * 40) + HIT_ZONE_COLUMN
sta COLRAM + (TRACK2_ROW * 40) + HIT_ZONE_COLUMN
sta COLRAM + (TRACK3_ROW * 40) + HIT_ZONE_COLUMN
jsr redraw_all_notes
rts
; ----------------------------------------------------------------------------
; Redraw All Notes
; ----------------------------------------------------------------------------
redraw_all_notes:
ldx #0
redraw_loop:
lda note_track,x
beq redraw_next
jsr draw_note
redraw_next:
inx
cpx #MAX_NOTES
bne redraw_loop
rts
; ----------------------------------------------------------------------------
; Update Border Flash
; ----------------------------------------------------------------------------
update_border_flash:
lda border_flash
beq flash_done
dec border_flash
bne flash_done
lda #BORDER_COL
sta BORDER
flash_done:
rts
; ----------------------------------------------------------------------------
; Check Keys
; ----------------------------------------------------------------------------
check_keys:
lda #$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
; ----------------------------------------------------------------------------
check_hit:
ldx #0
check_hit_loop:
lda note_track,x
beq check_hit_next
cmp key_pressed
bne check_hit_next
lda note_col,x
cmp #HIT_ZONE_MIN
bcc check_hit_next
cmp #HIT_ZONE_MAX+1
bcs check_hit_next
lda note_freq,x
sta hit_note_freq
lda note_col,x
cmp #HIT_ZONE_CENTRE
bcc hit_good
cmp #HIT_ZONE_CENTRE+2
bcs hit_good
lda #2
sta hit_quality
jmp hit_found
hit_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
; ----------------------------------------------------------------------------
; Award Points
; ----------------------------------------------------------------------------
award_points:
jsr increment_combo
lda hit_quality
cmp #2
beq award_perfect
lda #GOOD_SCORE
jsr apply_multiplier
jsr add_score
inc good_count
lda #GOOD_COL
sta BORDER
lda #4
sta border_flash
lda #HEALTH_GOOD
jsr increase_health
jmp award_done
award_perfect:
lda #PERFECT_SCORE
jsr apply_multiplier
jsr add_score
inc perfect_count
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
; ----------------------------------------------------------------------------
; 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
; ----------------------------------------------------------------------------
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
; ============================================================================
; SONG DATA
; ============================================================================
song_data:
!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
; ----------------------------------------------------------------------------
; 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
Try This: Animated Title
Add a simple animation to the title screen:
update_title:
; Cycle "PRESS FIRE" colour
inc title_timer
lda title_timer
and #$0F ; Every 16 frames
bne no_colour_change
lda press_fire_col
clc
adc #1
and #$0F ; Keep in range 0-15
sta press_fire_col
; Update colour RAM...
no_colour_change:
; Check fire...Cycling colours draw attention.
Try This: High Score on Title
Display the best score achieved on the title screen:
ldx #0
draw_high_score:
lda high_score_label,x
beq draw_high_done
sta SCREEN + (15 * 40) + 12,x
; ... display high_score value ...High scores encourage replay.
What You’ve Learnt
- State machines - Variables controlling code paths
- Title screen design - Clear title, instructions, call to action
- Fire button detection - CIA port for joystick input
- State transitions - Moving cleanly between game phases
- Game loop completion - Title → Play → Results → Title
What’s Next
In Unit 14, we’ll improve the game over screen. Currently it’s just “GAME OVER” overlaid on gameplay. We’ll give it the same treatment as the title screen - a dedicated display with score summary.
What Changed
Unit 12 → Unit 13
+245-86
| 1 | 1 | ; ============================================================================ | |
| 2 | - | ; SID SYMPHONY - Unit 12: Combo System | |
| 2 | + | ; SID SYMPHONY - Unit 13: Title Screen | |
| 3 | 3 | ; ============================================================================ | |
| 4 | - | ; Consecutive hits build a combo. Higher combos increase the score multiplier. | |
| 5 | - | ; Miss a note and the combo resets to zero. Consistency is rewarded. | |
| 4 | + | ; The game now starts with a proper title screen. Press fire to play. | |
| 5 | + | ; Complete game flow: Title -> Playing -> Results -> Title. | |
| 6 | 6 | ; | |
| 7 | 7 | ; Controls: Z = Track 1 (high), X = Track 2 (mid), C = Track 3 (low) | |
| 8 | + | ; Fire = Start game from title screen | |
| 8 | 9 | ; ============================================================================ | |
| 9 | 10 | | |
| 10 | 11 | ; ============================================================================ | |
| ... | |||
| 48 | 49 | | |
| 49 | 50 | HEALTH_COL = 5 | |
| 50 | 51 | PROGRESS_COL = 3 | |
| 51 | - | COMBO_COL = 13 ; Yellow for combo display | |
| 52 | + | COMBO_COL = 13 | |
| 53 | + | | |
| 54 | + | ; Title screen colours | |
| 55 | + | TITLE_COL = 1 ; White for title | |
| 56 | + | SUBTITLE_COL = 11 ; Grey for subtitle | |
| 52 | 57 | | |
| 53 | 58 | ; ============================================================================ | |
| 54 | 59 | ; SCORING SETTINGS | |
| ... | |||
| 61 | 66 | ; COMBO SETTINGS | |
| 62 | 67 | ; ============================================================================ | |
| 63 | 68 | | |
| 64 | - | COMBO_TIER_2 = 10 ; 2x multiplier at 10 combo | |
| 65 | - | COMBO_TIER_3 = 25 ; 3x multiplier at 25 combo | |
| 66 | - | COMBO_TIER_4 = 50 ; 4x multiplier at 50 combo | |
| 69 | + | COMBO_TIER_2 = 10 | |
| 70 | + | COMBO_TIER_3 = 25 | |
| 71 | + | COMBO_TIER_4 = 50 | |
| 67 | 72 | | |
| 68 | 73 | ; ============================================================================ | |
| 69 | 74 | ; HEALTH SETTINGS | |
| ... | |||
| 94 | 99 | ; GAME STATES | |
| 95 | 100 | ; ============================================================================ | |
| 96 | 101 | | |
| 97 | - | STATE_PLAYING = 0 | |
| 98 | - | STATE_RESULTS = 1 | |
| 99 | - | STATE_GAMEOVER = 2 | |
| 102 | + | STATE_TITLE = 0 ; NEW: Title screen | |
| 103 | + | STATE_PLAYING = 1 | |
| 104 | + | STATE_RESULTS = 2 | |
| 105 | + | STATE_GAMEOVER = 3 | |
| 100 | 106 | | |
| 101 | 107 | ; ============================================================================ | |
| 102 | 108 | ; MEMORY MAP | |
| ... | |||
| 135 | 141 | | |
| 136 | 142 | SID_VOLUME = $D418 | |
| 137 | 143 | | |
| 138 | - | ; CIA keyboard | |
| 144 | + | ; CIA keyboard and joystick | |
| 139 | 145 | CIA1_PRA = $DC00 | |
| 140 | 146 | CIA1_PRB = $DC01 | |
| 141 | 147 | | |
| ... | |||
| 150 | 156 | | |
| 151 | 157 | ; Combo display position | |
| 152 | 158 | COMBO_ROW = 2 | |
| 153 | - | COMBO_COL_POS = 17 | |
| 154 | 159 | | |
| 155 | 160 | ; Hit zone | |
| 156 | 161 | HIT_ZONE_COLUMN = 3 | |
| ... | |||
| 212 | 217 | | |
| 213 | 218 | start: | |
| 214 | 219 | jsr copy_charset | |
| 215 | - | jsr init_game | |
| 220 | + | jsr init_sid | |
| 221 | + | jsr show_title | |
| 222 | + | | |
| 223 | + | ; Start in TITLE state | |
| 224 | + | lda #STATE_TITLE | |
| 225 | + | sta game_state | |
| 216 | 226 | | |
| 217 | 227 | main_loop: | |
| 218 | 228 | lda #$FF | |
| ... | |||
| 221 | 231 | bne wait_raster | |
| 222 | 232 | | |
| 223 | 233 | lda game_state | |
| 234 | + | cmp #STATE_TITLE | |
| 235 | + | beq do_title | |
| 224 | 236 | cmp #STATE_PLAYING | |
| 225 | 237 | beq do_playing | |
| 226 | 238 | cmp #STATE_RESULTS | |
| 227 | 239 | beq do_results | |
| 228 | 240 | jmp do_gameover | |
| 241 | + | | |
| 242 | + | do_title: | |
| 243 | + | jsr update_title | |
| 244 | + | jmp main_loop | |
| 229 | 245 | | |
| 230 | 246 | do_playing: | |
| 231 | 247 | jsr update_playing | |
| ... | |||
| 240 | 256 | jmp main_loop | |
| 241 | 257 | | |
| 242 | 258 | ; ---------------------------------------------------------------------------- | |
| 243 | - | ; Initialize Game | |
| 259 | + | ; Show Title Screen | |
| 260 | + | ; ---------------------------------------------------------------------------- | |
| 261 | + | | |
| 262 | + | show_title: | |
| 263 | + | ; Clear screen | |
| 264 | + | lda #BORDER_COL | |
| 265 | + | sta BORDER | |
| 266 | + | lda #BG_COL | |
| 267 | + | sta BGCOL | |
| 268 | + | | |
| 269 | + | ldx #0 | |
| 270 | + | lda #CHAR_SPACE | |
| 271 | + | clear_title: | |
| 272 | + | sta SCREEN,x | |
| 273 | + | sta SCREEN+$100,x | |
| 274 | + | sta SCREEN+$200,x | |
| 275 | + | sta SCREEN+$2E8,x | |
| 276 | + | inx | |
| 277 | + | bne clear_title | |
| 278 | + | | |
| 279 | + | ; Draw big title "SID SYMPHONY" | |
| 280 | + | ldx #0 | |
| 281 | + | draw_title_text: | |
| 282 | + | lda title_big,x | |
| 283 | + | beq draw_title_done | |
| 284 | + | sta SCREEN + (8 * 40) + 14,x | |
| 285 | + | lda #TITLE_COL | |
| 286 | + | sta COLRAM + (8 * 40) + 14,x | |
| 287 | + | inx | |
| 288 | + | jmp draw_title_text | |
| 289 | + | draw_title_done: | |
| 290 | + | | |
| 291 | + | ; Draw subtitle "A RHYTHM GAME" | |
| 292 | + | ldx #0 | |
| 293 | + | draw_subtitle: | |
| 294 | + | lda subtitle_text,x | |
| 295 | + | beq draw_subtitle_done | |
| 296 | + | sta SCREEN + (10 * 40) + 13,x | |
| 297 | + | lda #SUBTITLE_COL | |
| 298 | + | sta COLRAM + (10 * 40) + 13,x | |
| 299 | + | inx | |
| 300 | + | jmp draw_subtitle | |
| 301 | + | draw_subtitle_done: | |
| 302 | + | | |
| 303 | + | ; Draw controls | |
| 304 | + | ldx #0 | |
| 305 | + | draw_controls: | |
| 306 | + | lda controls_text,x | |
| 307 | + | beq draw_controls_done | |
| 308 | + | sta SCREEN + (14 * 40) + 11,x | |
| 309 | + | lda #11 | |
| 310 | + | sta COLRAM + (14 * 40) + 11,x | |
| 311 | + | inx | |
| 312 | + | jmp draw_controls | |
| 313 | + | draw_controls_done: | |
| 314 | + | | |
| 315 | + | ; Draw track info | |
| 316 | + | ldx #0 | |
| 317 | + | draw_track_info: | |
| 318 | + | lda track_info,x | |
| 319 | + | beq draw_track_done | |
| 320 | + | sta SCREEN + (16 * 40) + 9,x | |
| 321 | + | lda #11 | |
| 322 | + | sta COLRAM + (16 * 40) + 9,x | |
| 323 | + | inx | |
| 324 | + | jmp draw_track_info | |
| 325 | + | draw_track_done: | |
| 326 | + | | |
| 327 | + | ; Draw "PRESS FIRE TO START" | |
| 328 | + | ldx #0 | |
| 329 | + | draw_press_fire: | |
| 330 | + | lda press_fire_text,x | |
| 331 | + | beq draw_press_done | |
| 332 | + | sta SCREEN + (20 * 40) + 10,x | |
| 333 | + | lda #7 ; Yellow | |
| 334 | + | sta COLRAM + (20 * 40) + 10,x | |
| 335 | + | inx | |
| 336 | + | jmp draw_press_fire | |
| 337 | + | draw_press_done: | |
| 338 | + | | |
| 339 | + | rts | |
| 340 | + | | |
| 341 | + | title_big: | |
| 342 | + | !scr "sid symphony" | |
| 343 | + | !byte 0 | |
| 344 | + | | |
| 345 | + | subtitle_text: | |
| 346 | + | !scr "a rhythm game" | |
| 347 | + | !byte 0 | |
| 348 | + | | |
| 349 | + | controls_text: | |
| 350 | + | !scr "controls: z / x / c" | |
| 351 | + | !byte 0 | |
| 352 | + | | |
| 353 | + | track_info: | |
| 354 | + | !scr "hit notes as they reach" | |
| 355 | + | !byte 0 | |
| 356 | + | | |
| 357 | + | press_fire_text: | |
| 358 | + | !scr "press fire to start" | |
| 359 | + | !byte 0 | |
| 360 | + | | |
| 361 | + | ; ---------------------------------------------------------------------------- | |
| 362 | + | ; Update Title State | |
| 363 | + | ; ---------------------------------------------------------------------------- | |
| 364 | + | | |
| 365 | + | update_title: | |
| 366 | + | ; Check for fire button (joystick port 2) | |
| 367 | + | lda CIA1_PRA | |
| 368 | + | and #$10 ; Bit 4 = fire | |
| 369 | + | beq fire_pressed | |
| 370 | + | | |
| 371 | + | ; Also check space bar as alternative | |
| 372 | + | lda #$7F | |
| 373 | + | sta CIA1_PRA | |
| 374 | + | lda CIA1_PRB | |
| 375 | + | and #$10 ; Space | |
| 376 | + | beq fire_pressed | |
| 377 | + | | |
| 378 | + | ; No input - stay on title | |
| 379 | + | lda #$FF | |
| 380 | + | sta CIA1_PRA | |
| 381 | + | rts | |
| 382 | + | | |
| 383 | + | fire_pressed: | |
| 384 | + | lda #$FF | |
| 385 | + | sta CIA1_PRA | |
| 386 | + | | |
| 387 | + | ; Start the game! | |
| 388 | + | jsr init_game | |
| 389 | + | lda #STATE_PLAYING | |
| 390 | + | sta game_state | |
| 391 | + | rts | |
| 392 | + | | |
| 393 | + | ; ---------------------------------------------------------------------------- | |
| 394 | + | ; Initialize Game (called when starting from title) | |
| 244 | 395 | ; ---------------------------------------------------------------------------- | |
| 245 | 396 | | |
| 246 | 397 | init_game: | |
| 247 | 398 | jsr init_screen | |
| 248 | - | jsr init_sid | |
| 249 | 399 | jsr init_notes | |
| 250 | 400 | jsr init_score | |
| 251 | 401 | jsr init_health | |
| 252 | 402 | jsr init_combo | |
| 253 | 403 | jsr init_song | |
| 254 | - | | |
| 255 | - | lda #STATE_PLAYING | |
| 256 | - | sta game_state | |
| 257 | 404 | | |
| 258 | 405 | rts | |
| 259 | 406 | | |
| ... | |||
| 297 | 444 | ; ---------------------------------------------------------------------------- | |
| 298 | 445 | | |
| 299 | 446 | update_results: | |
| 300 | - | lda #$00 | |
| 447 | + | ; Check for fire to return to title | |
| 448 | + | lda CIA1_PRA | |
| 449 | + | and #$10 | |
| 450 | + | beq results_fire | |
| 451 | + | | |
| 452 | + | ; Also check space bar | |
| 453 | + | lda #$7F | |
| 301 | 454 | sta CIA1_PRA | |
| 302 | 455 | lda CIA1_PRB | |
| 303 | - | cmp #$FF | |
| 304 | - | beq results_wait | |
| 456 | + | and #$10 | |
| 457 | + | beq results_fire | |
| 305 | 458 | | |
| 306 | - | jsr init_game | |
| 459 | + | lda #$FF | |
| 460 | + | sta CIA1_PRA | |
| 461 | + | rts | |
| 307 | 462 | | |
| 308 | - | results_wait: | |
| 463 | + | results_fire: | |
| 309 | 464 | lda #$FF | |
| 310 | 465 | sta CIA1_PRA | |
| 466 | + | | |
| 467 | + | ; Return to title screen | |
| 468 | + | jsr show_title | |
| 469 | + | lda #STATE_TITLE | |
| 470 | + | sta game_state | |
| 311 | 471 | rts | |
| 312 | 472 | | |
| 313 | 473 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 315 | 475 | ; ---------------------------------------------------------------------------- | |
| 316 | 476 | | |
| 317 | 477 | update_gameover: | |
| 318 | - | lda #$00 | |
| 478 | + | ; Check for fire to return to title | |
| 479 | + | lda CIA1_PRA | |
| 480 | + | and #$10 | |
| 481 | + | beq gameover_fire | |
| 482 | + | | |
| 483 | + | lda #$7F | |
| 319 | 484 | sta CIA1_PRA | |
| 320 | 485 | lda CIA1_PRB | |
| 321 | - | cmp #$FF | |
| 322 | - | beq gameover_wait | |
| 486 | + | and #$10 | |
| 487 | + | beq gameover_fire | |
| 323 | 488 | | |
| 324 | - | jsr init_game | |
| 489 | + | lda #$FF | |
| 490 | + | sta CIA1_PRA | |
| 491 | + | rts | |
| 325 | 492 | | |
| 326 | - | gameover_wait: | |
| 493 | + | gameover_fire: | |
| 327 | 494 | lda #$FF | |
| 328 | 495 | sta CIA1_PRA | |
| 496 | + | | |
| 497 | + | ; Return to title screen | |
| 498 | + | jsr show_title | |
| 499 | + | lda #STATE_TITLE | |
| 500 | + | sta game_state | |
| 329 | 501 | rts | |
| 330 | 502 | | |
| 331 | 503 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 441 | 613 | temp_progress: !byte 0 | |
| 442 | 614 | | |
| 443 | 615 | ; ---------------------------------------------------------------------------- | |
| 444 | - | ; Get Multiplier - Returns multiplier (1-4) based on combo | |
| 616 | + | ; Get Multiplier | |
| 445 | 617 | ; ---------------------------------------------------------------------------- | |
| 446 | 618 | | |
| 447 | 619 | get_multiplier: | |
| ... | |||
| 453 | 625 | cmp #COMBO_TIER_2 | |
| 454 | 626 | bcs mult_2x | |
| 455 | 627 | | |
| 456 | - | ; Default: 1x | |
| 457 | 628 | lda #1 | |
| 458 | 629 | rts | |
| 459 | 630 | | |
| ... | |||
| 474 | 645 | ; ---------------------------------------------------------------------------- | |
| 475 | 646 | | |
| 476 | 647 | display_combo: | |
| 477 | - | ; Draw "COMBO:" label | |
| 478 | 648 | ldx #0 | |
| 479 | 649 | draw_combo_label: | |
| 480 | 650 | lda combo_label,x | |
| ... | |||
| 486 | 656 | jmp draw_combo_label | |
| 487 | 657 | | |
| 488 | 658 | draw_combo_value: | |
| 489 | - | ; Display 3-digit combo value | |
| 490 | 659 | lda combo | |
| 491 | 660 | | |
| 492 | - | ; Hundreds | |
| 493 | 661 | ldx #0 | |
| 494 | 662 | combo_div_100: | |
| 495 | 663 | cmp #100 | |
| ... | |||
| 505 | 673 | sta SCREEN + (COMBO_ROW * 40) + 18 | |
| 506 | 674 | pla | |
| 507 | 675 | | |
| 508 | - | ; Tens | |
| 509 | 676 | ldx #0 | |
| 510 | 677 | combo_div_10: | |
| 511 | 678 | cmp #10 | |
| ... | |||
| 521 | 688 | sta SCREEN + (COMBO_ROW * 40) + 19 | |
| 522 | 689 | pla | |
| 523 | 690 | | |
| 524 | - | ; Ones | |
| 525 | 691 | ora #$30 | |
| 526 | 692 | sta SCREEN + (COMBO_ROW * 40) + 20 | |
| 527 | 693 | | |
| 528 | - | ; Colour based on multiplier tier | |
| 529 | 694 | jsr get_multiplier | |
| 530 | 695 | cmp #4 | |
| 531 | 696 | beq combo_col_4x | |
| ... | |||
| 534 | 699 | cmp #2 | |
| 535 | 700 | beq combo_col_2x | |
| 536 | 701 | | |
| 537 | - | ; 1x = grey | |
| 538 | 702 | lda #11 | |
| 539 | 703 | jmp set_combo_col | |
| 540 | 704 | | |
| 541 | 705 | combo_col_2x: | |
| 542 | - | lda #7 ; Yellow | |
| 706 | + | lda #7 | |
| 543 | 707 | jmp set_combo_col | |
| 544 | 708 | | |
| 545 | 709 | combo_col_3x: | |
| 546 | - | lda #5 ; Green | |
| 710 | + | lda #5 | |
| 547 | 711 | jmp set_combo_col | |
| 548 | 712 | | |
| 549 | 713 | combo_col_4x: | |
| 550 | - | lda #1 ; White (best) | |
| 714 | + | lda #1 | |
| 551 | 715 | | |
| 552 | 716 | set_combo_col: | |
| 553 | 717 | sta COLRAM + (COMBO_ROW * 40) + 18 | |
| 554 | 718 | sta COLRAM + (COMBO_ROW * 40) + 19 | |
| 555 | 719 | sta COLRAM + (COMBO_ROW * 40) + 20 | |
| 556 | 720 | | |
| 557 | - | ; Display multiplier | |
| 558 | 721 | jsr get_multiplier | |
| 559 | 722 | ora #$30 | |
| 560 | 723 | sta SCREEN + (COMBO_ROW * 40) + 22 | |
| 561 | - | lda #$18 ; 'x' character | |
| 724 | + | lda #$18 | |
| 562 | 725 | sta SCREEN + (COMBO_ROW * 40) + 23 | |
| 563 | 726 | | |
| 564 | 727 | jsr get_multiplier | |
| ... | |||
| 600 | 763 | increment_combo: | |
| 601 | 764 | inc combo | |
| 602 | 765 | | |
| 603 | - | ; Update max combo if needed | |
| 604 | 766 | lda combo | |
| 605 | 767 | cmp max_combo | |
| 606 | 768 | bcc combo_not_max | |
| ... | |||
| 618 | 780 | lda combo | |
| 619 | 781 | beq combo_already_zero | |
| 620 | 782 | | |
| 621 | - | ; Combo was active - show break | |
| 622 | 783 | lda #0 | |
| 623 | 784 | sta combo | |
| 624 | 785 | jsr display_combo | |
| ... | |||
| 631 | 792 | ; ---------------------------------------------------------------------------- | |
| 632 | 793 | | |
| 633 | 794 | show_results: | |
| 634 | - | ; Clear screen | |
| 635 | 795 | ldx #0 | |
| 636 | 796 | lda #CHAR_SPACE | |
| 637 | 797 | clear_for_results: | |
| ... | |||
| 642 | 802 | inx | |
| 643 | 803 | bne clear_for_results | |
| 644 | 804 | | |
| 645 | - | ; Title | |
| 646 | 805 | ldx #0 | |
| 647 | 806 | draw_results_title: | |
| 648 | 807 | lda results_title,x | |
| ... | |||
| 654 | 813 | jmp draw_results_title | |
| 655 | 814 | draw_results_title_done: | |
| 656 | 815 | | |
| 657 | - | ; Score | |
| 658 | 816 | ldx #0 | |
| 659 | 817 | draw_final_score_label: | |
| 660 | 818 | lda final_score_label,x | |
| ... | |||
| 667 | 825 | draw_final_score_done: | |
| 668 | 826 | jsr display_final_score | |
| 669 | 827 | | |
| 670 | - | ; Perfects | |
| 671 | 828 | ldx #0 | |
| 672 | 829 | draw_perfects_label: | |
| 673 | 830 | lda perfects_label,x | |
| ... | |||
| 681 | 838 | lda perfect_count | |
| 682 | 839 | jsr display_stat_at_8 | |
| 683 | 840 | | |
| 684 | - | ; Goods | |
| 685 | 841 | ldx #0 | |
| 686 | 842 | draw_goods_label: | |
| 687 | 843 | lda goods_label,x | |
| ... | |||
| 695 | 851 | lda good_count | |
| 696 | 852 | jsr display_stat_at_9 | |
| 697 | 853 | | |
| 698 | - | ; Misses | |
| 699 | 854 | ldx #0 | |
| 700 | 855 | draw_misses_label: | |
| 701 | 856 | lda misses_label,x | |
| ... | |||
| 709 | 864 | lda miss_count | |
| 710 | 865 | jsr display_stat_at_10 | |
| 711 | 866 | | |
| 712 | - | ; Max Combo | |
| 713 | 867 | ldx #0 | |
| 714 | 868 | draw_max_combo_label: | |
| 715 | 869 | lda max_combo_label,x | |
| ... | |||
| 723 | 877 | lda max_combo | |
| 724 | 878 | jsr display_stat_at_12 | |
| 725 | 879 | | |
| 726 | - | ; Accuracy | |
| 727 | 880 | ldx #0 | |
| 728 | 881 | draw_accuracy_label: | |
| 729 | 882 | lda accuracy_label,x | |
| ... | |||
| 737 | 890 | jsr calculate_accuracy | |
| 738 | 891 | jsr display_accuracy | |
| 739 | 892 | | |
| 740 | - | ; Press any key | |
| 741 | 893 | ldx #0 | |
| 742 | 894 | draw_press_key: | |
| 743 | - | lda press_key_text,x | |
| 895 | + | lda press_fire_results,x | |
| 744 | 896 | beq draw_press_key_done | |
| 745 | - | sta SCREEN + (18 * 40) + 10,x | |
| 746 | - | lda #11 | |
| 747 | - | sta COLRAM + (18 * 40) + 10,x | |
| 897 | + | sta SCREEN + (18 * 40) + 9,x | |
| 898 | + | lda #7 | |
| 899 | + | sta COLRAM + (18 * 40) + 9,x | |
| 748 | 900 | inx | |
| 749 | 901 | jmp draw_press_key | |
| 750 | 902 | draw_press_key_done: | |
| ... | |||
| 782 | 934 | !scr "accuracy:" | |
| 783 | 935 | !byte 0 | |
| 784 | 936 | | |
| 785 | - | press_key_text: | |
| 786 | - | !scr "press any key" | |
| 937 | + | press_fire_results: | |
| 938 | + | !scr "press fire for title" | |
| 787 | 939 | !byte 0 | |
| 788 | 940 | | |
| 789 | 941 | ; ---------------------------------------------------------------------------- | |
| 790 | - | ; Display Final Score (at row 6) | |
| 942 | + | ; Display Final Score | |
| 791 | 943 | ; ---------------------------------------------------------------------------- | |
| 792 | 944 | | |
| 793 | 945 | display_final_score: | |
| ... | |||
| 874 | 1026 | rts | |
| 875 | 1027 | | |
| 876 | 1028 | ; ---------------------------------------------------------------------------- | |
| 877 | - | ; Display Stat (2-digit) at various rows | |
| 1029 | + | ; Display Stats | |
| 878 | 1030 | ; ---------------------------------------------------------------------------- | |
| 879 | 1031 | | |
| 880 | 1032 | display_stat_at_8: | |
| ... | |||
| 1080 | 1232 | rts | |
| 1081 | 1233 | | |
| 1082 | 1234 | ; ---------------------------------------------------------------------------- | |
| 1083 | - | ; Copy Character Set from ROM to RAM | |
| 1235 | + | ; Copy Character Set | |
| 1084 | 1236 | ; ---------------------------------------------------------------------------- | |
| 1085 | 1237 | | |
| 1086 | 1238 | copy_charset: | |
| ... | |||
| 1347 | 1499 | rts | |
| 1348 | 1500 | | |
| 1349 | 1501 | ; ---------------------------------------------------------------------------- | |
| 1350 | - | ; Handle Miss - Now breaks combo | |
| 1502 | + | ; Handle Miss | |
| 1351 | 1503 | ; ---------------------------------------------------------------------------- | |
| 1352 | 1504 | | |
| 1353 | 1505 | handle_miss: | |
| ... | |||
| 1362 | 1514 | | |
| 1363 | 1515 | jsr display_misses | |
| 1364 | 1516 | jsr decrease_health | |
| 1365 | - | | |
| 1366 | - | ; Break the combo! | |
| 1367 | 1517 | jsr break_combo | |
| 1368 | 1518 | | |
| 1369 | 1519 | rts | |
| ... | |||
| 1427 | 1577 | ldx #0 | |
| 1428 | 1578 | game_over_loop: | |
| 1429 | 1579 | lda game_over_text,x | |
| 1430 | - | beq game_over_done | |
| 1431 | - | sta SCREEN + (12 * 40) + 15,x | |
| 1580 | + | beq game_over_text_done | |
| 1581 | + | sta SCREEN + (10 * 40) + 15,x | |
| 1432 | 1582 | lda #2 | |
| 1433 | - | sta COLRAM + (12 * 40) + 15,x | |
| 1583 | + | sta COLRAM + (10 * 40) + 15,x | |
| 1434 | 1584 | inx | |
| 1435 | 1585 | jmp game_over_loop | |
| 1586 | + | game_over_text_done: | |
| 1587 | + | | |
| 1588 | + | ldx #0 | |
| 1589 | + | game_over_press: | |
| 1590 | + | lda press_fire_gameover,x | |
| 1591 | + | beq game_over_done | |
| 1592 | + | sta SCREEN + (14 * 40) + 9,x | |
| 1593 | + | lda #7 | |
| 1594 | + | sta COLRAM + (14 * 40) + 9,x | |
| 1595 | + | inx | |
| 1596 | + | jmp game_over_press | |
| 1597 | + | | |
| 1436 | 1598 | game_over_done: | |
| 1437 | 1599 | lda #2 | |
| 1438 | 1600 | sta BORDER | |
| ... | |||
| 1440 | 1602 | | |
| 1441 | 1603 | game_over_text: | |
| 1442 | 1604 | !scr "game over" | |
| 1605 | + | !byte 0 | |
| 1606 | + | | |
| 1607 | + | press_fire_gameover: | |
| 1608 | + | !scr "press fire for title" | |
| 1443 | 1609 | !byte 0 | |
| 1444 | 1610 | | |
| 1445 | 1611 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 1802 | 1968 | draw_miss_label_done: | |
| 1803 | 1969 | | |
| 1804 | 1970 | ldx #0 | |
| 1805 | - | draw_title: | |
| 1806 | - | lda title_text,x | |
| 1807 | - | beq draw_title_done | |
| 1971 | + | draw_title_game: | |
| 1972 | + | lda title_game,x | |
| 1973 | + | beq draw_title_game_done | |
| 1808 | 1974 | sta SCREEN + 27,x | |
| 1809 | 1975 | lda #1 | |
| 1810 | 1976 | sta COLRAM + 27,x | |
| 1811 | 1977 | inx | |
| 1812 | - | bne draw_title | |
| 1813 | - | draw_title_done: | |
| 1978 | + | bne draw_title_game | |
| 1979 | + | draw_title_game_done: | |
| 1814 | 1980 | | |
| 1815 | 1981 | ldx #0 | |
| 1816 | 1982 | draw_health_label: | |
| ... | |||
| 1859 | 2025 | !scr "miss:" | |
| 1860 | 2026 | !byte 0 | |
| 1861 | 2027 | | |
| 1862 | - | title_text: | |
| 2028 | + | title_game: | |
| 1863 | 2029 | !scr "sid symphony" | |
| 1864 | 2030 | !byte 0 | |
| 1865 | 2031 | | |
| ... | |||
| 2103 | 2269 | rts | |
| 2104 | 2270 | | |
| 2105 | 2271 | ; ---------------------------------------------------------------------------- | |
| 2106 | - | ; Award Points - Now uses combo multiplier | |
| 2272 | + | ; Award Points | |
| 2107 | 2273 | ; ---------------------------------------------------------------------------- | |
| 2108 | 2274 | | |
| 2109 | 2275 | award_points: | |
| 2110 | - | ; Increment combo first | |
| 2111 | 2276 | jsr increment_combo | |
| 2112 | 2277 | | |
| 2113 | - | ; Get base score | |
| 2114 | 2278 | lda hit_quality | |
| 2115 | 2279 | cmp #2 | |
| 2116 | 2280 | beq award_perfect | |
| 2117 | 2281 | | |
| 2118 | - | ; Good hit: 50 * multiplier | |
| 2119 | 2282 | lda #GOOD_SCORE | |
| 2120 | 2283 | jsr apply_multiplier | |
| 2121 | 2284 | jsr add_score | |
| ... | |||
| 2133 | 2296 | jmp award_done | |
| 2134 | 2297 | | |
| 2135 | 2298 | award_perfect: | |
| 2136 | - | ; Perfect hit: 100 * multiplier | |
| 2137 | 2299 | lda #PERFECT_SCORE | |
| 2138 | 2300 | jsr apply_multiplier | |
| 2139 | 2301 | jsr add_score | |
| ... | |||
| 2153 | 2315 | rts | |
| 2154 | 2316 | | |
| 2155 | 2317 | ; ---------------------------------------------------------------------------- | |
| 2156 | - | ; Apply Multiplier - A = base score, returns multiplied score in score_add_lo/hi | |
| 2318 | + | ; Apply Multiplier | |
| 2157 | 2319 | ; ---------------------------------------------------------------------------- | |
| 2158 | 2320 | | |
| 2159 | 2321 | apply_multiplier: | |
| ... | |||
| 2161 | 2323 | jsr get_multiplier | |
| 2162 | 2324 | sta current_mult | |
| 2163 | 2325 | | |
| 2164 | - | ; Start with base score | |
| 2165 | 2326 | lda base_score | |
| 2166 | 2327 | sta score_add_lo | |
| 2167 | 2328 | lda #0 | |
| 2168 | 2329 | sta score_add_hi | |
| 2169 | 2330 | | |
| 2170 | - | ; If multiplier is 1, we're done | |
| 2171 | 2331 | lda current_mult | |
| 2172 | 2332 | cmp #1 | |
| 2173 | 2333 | beq mult_done_apply | |
| 2174 | 2334 | | |
| 2175 | - | ; Multiply by adding base_score (mult-1) more times | |
| 2176 | 2335 | dec current_mult | |
| 2177 | 2336 | mult_add_loop: | |
| 2178 | 2337 | lda score_add_lo | |
| ... | |||
| 2194 | 2353 | score_add_hi: !byte 0 | |
| 2195 | 2354 | | |
| 2196 | 2355 | ; ---------------------------------------------------------------------------- | |
| 2197 | - | ; Add Score - Adds score_add_lo/hi to score | |
| 2356 | + | ; Add Score | |
| 2198 | 2357 | ; ---------------------------------------------------------------------------- | |
| 2199 | 2358 | | |
| 2200 | 2359 | add_score: | |
| ... | |||
| 2328 | 2487 | work_hi: !byte 0 | |
| 2329 | 2488 | | |
| 2330 | 2489 | ; ---------------------------------------------------------------------------- | |
| 2331 | - | ; Play Voices With Note Frequency | |
| 2490 | + | ; Play Voices | |
| 2332 | 2491 | ; ---------------------------------------------------------------------------- | |
| 2333 | 2492 | | |
| 2334 | 2493 | play_voice1_note: | |
| ... | |||
| 2362 | 2521 | rts | |
| 2363 | 2522 | | |
| 2364 | 2523 | ; ---------------------------------------------------------------------------- | |
| 2365 | - | ; Flash Tracks on Hit | |
| 2524 | + | ; Flash Tracks | |
| 2366 | 2525 | ; ---------------------------------------------------------------------------- | |
| 2367 | 2526 | | |
| 2368 | 2527 | flash_track1_hit: |