Game 1 Unit 10 of 64 1 hr learning time
Song Playback
Play the song from data. Progress bar shows how far through. The rhythm feels right.
16% of SID Symphony
Players need to know where they are in the song. This unit adds progress tracking.
A progress bar shows how far through the song the player has reached. Each beat advances the bar. Players can see the end approaching. It creates anticipation - “just a bit more” or “almost there.”
Run It
Assemble and run:
acme -f cbm -o symphony.prg symphony.asm
Watch the cyan progress bar at the bottom. It fills as the song plays. The health bar above it shows your performance. Two measures of progress - through the song and through survival.
Tracking Song Position
A new variable tracks the current beat within the song:
; ----------------------------------------------------------------------------
; Song Variables
; ----------------------------------------------------------------------------
SONG_LENGTH = 64 ; Total beats in the song
PROGRESS_WIDTH = 16 ; Width of progress bar in characters
song_beat = $0D ; Current beat in song (0 to SONG_LENGTH-1)
; ----------------------------------------------------------------------------
; Advance Song - Increment beat and update progress
; ----------------------------------------------------------------------------
advance_song:
inc beat_count
inc song_beat
; Check if song has ended
lda song_beat
cmp #SONG_LENGTH
bcc song_continues
; Song loops for now (Unit 11 will add proper end)
lda #0
sta song_beat
sta beat_count
lda #<song_data
sta song_pos
lda #>song_data
sta song_pos_hi
song_continues:
jsr display_progress
rts
The song_beat variable counts from 0 to 63 (SONG_LENGTH minus 1). Each beat increments it. When it reaches SONG_LENGTH, the song loops back to the start.
The Progress Bar
The progress bar converts song position to visual representation:
; ----------------------------------------------------------------------------
; Display Progress - Show song progress bar
; ----------------------------------------------------------------------------
display_progress:
; Calculate progress: (song_beat * PROGRESS_WIDTH) / SONG_LENGTH
; For 64-beat song with 16-char bar: song_beat / 4
lda song_beat
lsr ; Divide by 4
lsr
sta temp_progress
; Draw filled portion
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 ; Dark grey
sta COLRAM + (PROGRESS_ROW * 40) + 12,x
inx
jmp draw_empty_progress
progress_done:
rts
temp_progress: !byte 0
The calculation uses bit shifting for division. With a 64-beat song and 16-character bar, each character represents 4 beats. Two LSR instructions divide by 4. The result tells us how many filled blocks to draw.
Why Progress Matters
Progress creates emotional engagement:
- Early song - Full bar ahead feels daunting
- Midway - Momentum builds, player feels committed
- Near end - Tension peaks, “almost there” excitement
- Complete - Satisfaction of finishing
Without progress indication, players don’t know if they’re at beat 10 or beat 50. The bar transforms an abstract challenge into a visible journey.
Layout Considerations
The screen now shows two bars:
Row 23: HEALTH: [########........]
Row 24: SONG: [####............]Health shows performance quality. Progress shows song position. Two complementary pieces of information. The player knows both “how am I doing?” and “how far to go?”
The Main Loop
The main loop now calls advance_song each beat:
no_new_beat:
; ...
jmp main_loop
; Called once per beat
advance_song:
inc beat_count
inc song_beat
; Check for song end
; Update progress displayThe beat counter drives everything - note spawning, song position, progress display. One timing system controls all game events.
The Complete Code
; ============================================================================
; SID SYMPHONY - Unit 10: Song Playback
; ============================================================================
; Song plays with proper timing. Progress bar shows how far through the song.
; Notes spawn at exactly the right beat. The rhythm feels right.
;
; Controls: Z = Track 1 (high), X = Track 2 (mid), C = Track 3 (low)
; ============================================================================
; ============================================================================
; CUSTOMISATION SECTION
; ============================================================================
; SID Voice Settings
VOICE1_WAVE = $21 ; Sawtooth
VOICE2_WAVE = $41 ; Pulse
VOICE3_WAVE = $11 ; Triangle
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 ; Cyan for progress bar
; ============================================================================
; SCORING SETTINGS
; ============================================================================
PERFECT_SCORE = 100
GOOD_SCORE = 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 ; Total beats in the song
PROGRESS_WIDTH = 16 ; Width of progress bar in characters
; ============================================================================
; 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
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
; 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
; 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_over = $0B
hit_note_freq = $0C
song_beat = $0D ; Current beat in song (0 to SONG_LENGTH-1)
; ----------------------------------------------------------------------------
; BASIC Stub
; ----------------------------------------------------------------------------
* = $0801
!byte $0C, $08
!byte $0A, $00
!byte $9E
!text "2064"
!byte $00
!byte $00, $00
; ----------------------------------------------------------------------------
; Main Program
; ----------------------------------------------------------------------------
* = $0810
start:
jsr copy_charset
jsr init_screen
jsr init_sid
jsr init_notes
jsr init_score
jsr init_health
jsr init_song
main_loop:
lda #$FF
wait_raster:
cmp $D012
bne wait_raster
lda game_over
bne main_loop
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
jmp main_loop
; ----------------------------------------------------------------------------
; 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 game_over
jsr display_progress
rts
; ----------------------------------------------------------------------------
; Advance Song - Increment beat and update progress
; ----------------------------------------------------------------------------
advance_song:
inc beat_count
inc song_beat
; Check if song has ended
lda song_beat
cmp #SONG_LENGTH
bcc song_continues
; Song loops for now (Unit 11 will add proper end)
lda #0
sta song_beat
sta beat_count
lda #<song_data
sta song_pos
lda #>song_data
sta song_pos_hi
song_continues:
jsr display_progress
rts
; ----------------------------------------------------------------------------
; Display Progress - Show song progress bar
; ----------------------------------------------------------------------------
display_progress:
; Calculate progress: (song_beat * PROGRESS_WIDTH) / SONG_LENGTH
; For 64-beat song with 16-char bar: song_beat / 4
lda song_beat
lsr ; Divide by 4
lsr
sta temp_progress
; Draw filled portion
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 ; Dark grey
sta COLRAM + (PROGRESS_ROW * 40) + 12,x
inx
jmp draw_empty_progress
progress_done:
rts
temp_progress: !byte 0
; ----------------------------------------------------------------------------
; Copy Character Set from ROM to RAM
; ----------------------------------------------------------------------------
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
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:
ldy #0
spawn_check_loop:
lda (song_pos),y
cmp #$FF
beq spawn_done ; Don't auto-restart here
cmp beat_count
beq spawn_match
bcs spawn_done
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_done:
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
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 #1
sta game_over
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_done
sta SCREEN + (12 * 40) + 15,x
lda #2
sta COLRAM + (12 * 40) + 15,x
inx
jmp game_over_loop
game_over_done:
lda #2
sta BORDER
rts
game_over_text:
!scr "game over"
!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:
lda title_text,x
beq draw_title_done
sta SCREEN + 27,x
lda #1
sta COLRAM + 27,x
inx
bne draw_title
draw_title_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_text:
!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:
lda hit_quality
cmp #2
beq award_perfect
lda score_lo
clc
adc #GOOD_SCORE
sta score_lo
lda score_hi
adc #0
sta score_hi
lda #GOOD_COL
sta BORDER
lda #4
sta border_flash
lda #HEALTH_GOOD
jsr increase_health
jmp award_done
award_perfect:
lda score_lo
clc
adc #PERFECT_SCORE
sta score_lo
lda score_hi
adc #0
sta score_hi
lda #PERFECT_COL
sta BORDER
lda #6
sta border_flash
lda #HEALTH_PERFECT
jsr increase_health
award_done:
jsr display_score
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 With Note Frequency
; ----------------------------------------------------------------------------
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 on Hit
; ----------------------------------------------------------------------------
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:
; Bar 1
!byte 0, 1, $47
!byte 2, 2, $2C
!byte 4, 3, $11
; Bar 2
!byte 8, 1, $3B
!byte 10, 2, $27
!byte 12, 3, $13
; Bar 3
!byte 16, 1, $35
!byte 17, 2, $2C
!byte 18, 1, $3B
!byte 20, 3, $16
; Bar 4
!byte 24, 1, $47
!byte 26, 2, $35
!byte 28, 3, $11
; Bar 5
!byte 32, 2, $2F
!byte 34, 1, $4F
!byte 36, 3, $17
; Bar 6
!byte 40, 1, $58
!byte 42, 2, $2C
!byte 44, 3, $11
!byte 46, 2, $27
; Bar 7
!byte 48, 1, $6A
!byte 49, 2, $35
!byte 50, 1, $58
!byte 52, 3, $1A
!byte 54, 2, $2F
; Bar 8
!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
health: !byte 0
Try This: Different Bar Colours
Change the progress bar colour based on position:
display_progress:
lda song_beat
cmp #48 ; Last quarter
bcs progress_yellow
lda #3 ; Cyan
jmp set_progress_col
progress_yellow:
lda #7 ; Yellow when near end
set_progress_col:
sta progress_colourYellow in the final stretch heightens tension.
Try This: Percentage Display
Add a numeric percentage:
; After updating bar
lda song_beat
; Multiply by 100, divide by 64
; (or approximate: song_beat * 3 / 2)
; Display two digitsNumbers complement the visual bar.
What You’ve Learnt
- Progress tracking - Counting beats through the song
- Visual progress bars - Converting numbers to filled blocks
- Player psychology - How progress indication affects engagement
- Screen layout - Organising multiple status displays
What’s Next
In Unit 11, we’ll handle the song end properly. When the song finishes, the game shows results - final score, accuracy percentage, and whether you succeeded or failed. The loop becomes a complete experience.
What Changed
Unit 9 → Unit 10
+193-126
| 1 | 1 | ; ============================================================================ | |
| 2 | - | ; SID SYMPHONY - Unit 9: Song Data | |
| 2 | + | ; SID SYMPHONY - Unit 10: Song Playback | |
| 3 | 3 | ; ============================================================================ | |
| 4 | - | ; Design the song data format. Create the first complete musical pattern. | |
| 5 | - | ; Notes now carry pitch information - each hit plays its actual note. | |
| 4 | + | ; Song plays with proper timing. Progress bar shows how far through the song. | |
| 5 | + | ; Notes spawn at exactly the right beat. The rhythm feels right. | |
| 6 | 6 | ; | |
| 7 | 7 | ; Controls: Z = Track 1 (high), X = Track 2 (mid), C = Track 3 (low) | |
| 8 | 8 | ; ============================================================================ | |
| ... | |||
| 11 | 11 | ; CUSTOMISATION SECTION | |
| 12 | 12 | ; ============================================================================ | |
| 13 | 13 | | |
| 14 | - | ; SID Voice Settings (default for when no note playing) | |
| 14 | + | ; SID Voice Settings | |
| 15 | 15 | VOICE1_WAVE = $21 ; Sawtooth | |
| 16 | 16 | VOICE2_WAVE = $41 ; Pulse | |
| 17 | 17 | VOICE3_WAVE = $11 ; Triangle | |
| 18 | 18 | | |
| 19 | - | ; Default frequencies (used if no note data) | |
| 20 | - | VOICE1_FREQ = $1C ; High pitch | |
| 21 | - | VOICE2_FREQ = $0E ; Mid pitch | |
| 22 | - | VOICE3_FREQ = $07 ; Low pitch | |
| 19 | + | VOICE1_FREQ = $1C | |
| 20 | + | VOICE2_FREQ = $0E | |
| 21 | + | VOICE3_FREQ = $07 | |
| 23 | 22 | | |
| 24 | - | VOICE_AD = $09 ; Attack=0, Decay=9 | |
| 25 | - | VOICE_SR = $00 ; Sustain=0, Release=0 | |
| 26 | - | PULSE_WIDTH = $08 ; 50% duty cycle | |
| 23 | + | VOICE_AD = $09 | |
| 24 | + | VOICE_SR = $00 | |
| 25 | + | PULSE_WIDTH = $08 | |
| 27 | 26 | | |
| 28 | 27 | ; Miss sound settings | |
| 29 | - | MISS_FREQ = $08 ; Low rumble | |
| 30 | - | MISS_WAVE = $81 ; Noise waveform | |
| 31 | - | MISS_AD = $00 ; Instant attack, no decay | |
| 32 | - | MISS_SR = $90 ; High sustain, fast release | |
| 28 | + | MISS_FREQ = $08 | |
| 29 | + | MISS_WAVE = $81 | |
| 30 | + | MISS_AD = $00 | |
| 31 | + | MISS_SR = $90 | |
| 33 | 32 | | |
| 34 | 33 | ; Visual Settings | |
| 35 | - | BORDER_COL = 0 ; Black border | |
| 36 | - | BG_COL = 0 ; Black background | |
| 34 | + | BORDER_COL = 0 | |
| 35 | + | BG_COL = 0 | |
| 37 | 36 | | |
| 38 | - | TRACK1_NOTE_COL = 10 ; Light red | |
| 39 | - | TRACK2_NOTE_COL = 13 ; Light green | |
| 40 | - | TRACK3_NOTE_COL = 14 ; Light blue | |
| 37 | + | TRACK1_NOTE_COL = 10 | |
| 38 | + | TRACK2_NOTE_COL = 13 | |
| 39 | + | TRACK3_NOTE_COL = 14 | |
| 41 | 40 | | |
| 42 | - | TRACK_LINE_COL = 11 ; Dark grey | |
| 43 | - | HIT_ZONE_COL = 7 ; Yellow | |
| 41 | + | TRACK_LINE_COL = 11 | |
| 42 | + | HIT_ZONE_COL = 7 | |
| 44 | 43 | | |
| 45 | - | HIT_COL = 1 ; White - flash on successful hit | |
| 46 | - | PERFECT_COL = 1 ; White - perfect hit border flash | |
| 47 | - | GOOD_COL = 7 ; Yellow - good hit border flash | |
| 48 | - | MISS_COL = 2 ; Red - miss border flash | |
| 44 | + | HIT_COL = 1 | |
| 45 | + | PERFECT_COL = 1 | |
| 46 | + | GOOD_COL = 7 | |
| 47 | + | MISS_COL = 2 | |
| 49 | 48 | | |
| 50 | - | HEALTH_COL = 5 ; Green for health bar | |
| 49 | + | HEALTH_COL = 5 | |
| 50 | + | PROGRESS_COL = 3 ; Cyan for progress bar | |
| 51 | 51 | | |
| 52 | 52 | ; ============================================================================ | |
| 53 | 53 | ; SCORING SETTINGS | |
| ... | |||
| 78 | 78 | ; SONG SETTINGS | |
| 79 | 79 | ; ============================================================================ | |
| 80 | 80 | | |
| 81 | - | SONG_LENGTH = 64 ; Beats in the song | |
| 81 | + | SONG_LENGTH = 64 ; Total beats in the song | |
| 82 | + | PROGRESS_WIDTH = 16 ; Width of progress bar in characters | |
| 82 | 83 | | |
| 83 | 84 | ; ============================================================================ | |
| 84 | 85 | ; MEMORY MAP | |
| ... | |||
| 126 | 127 | TRACK2_ROW = 12 | |
| 127 | 128 | TRACK3_ROW = 16 | |
| 128 | 129 | | |
| 129 | - | ; Health bar position | |
| 130 | + | ; HUD positions | |
| 130 | 131 | HEALTH_ROW = 23 | |
| 132 | + | PROGRESS_ROW = 24 | |
| 131 | 133 | | |
| 132 | 134 | ; Hit zone | |
| 133 | 135 | HIT_ZONE_COLUMN = 3 | |
| ... | |||
| 162 | 164 | border_flash = $09 | |
| 163 | 165 | miss_track = $0A | |
| 164 | 166 | game_over = $0B | |
| 165 | - | hit_note_freq = $0C ; Frequency of note being hit | |
| 167 | + | hit_note_freq = $0C | |
| 168 | + | song_beat = $0D ; Current beat in song (0 to SONG_LENGTH-1) | |
| 166 | 169 | | |
| 167 | 170 | ; ---------------------------------------------------------------------------- | |
| 168 | 171 | ; BASIC Stub | |
| ... | |||
| 190 | 193 | jsr init_notes | |
| 191 | 194 | jsr init_score | |
| 192 | 195 | jsr init_health | |
| 193 | - | | |
| 194 | - | lda #<song_data | |
| 195 | - | sta song_pos | |
| 196 | - | lda #>song_data | |
| 197 | - | sta song_pos_hi | |
| 198 | - | | |
| 199 | - | lda #0 | |
| 200 | - | sta frame_count | |
| 201 | - | sta beat_count | |
| 202 | - | sta border_flash | |
| 203 | - | sta game_over | |
| 196 | + | jsr init_song | |
| 204 | 197 | | |
| 205 | 198 | main_loop: | |
| 206 | 199 | lda #$FF | |
| ... | |||
| 218 | 211 | | |
| 219 | 212 | lda #0 | |
| 220 | 213 | sta frame_count | |
| 214 | + | jsr advance_song | |
| 221 | 215 | jsr check_spawn_note | |
| 222 | - | inc beat_count | |
| 223 | 216 | | |
| 224 | 217 | no_new_beat: | |
| 225 | 218 | jsr update_notes | |
| ... | |||
| 228 | 221 | jsr check_keys | |
| 229 | 222 | | |
| 230 | 223 | jmp main_loop | |
| 224 | + | | |
| 225 | + | ; ---------------------------------------------------------------------------- | |
| 226 | + | ; Initialize Song | |
| 227 | + | ; ---------------------------------------------------------------------------- | |
| 228 | + | | |
| 229 | + | init_song: | |
| 230 | + | lda #<song_data | |
| 231 | + | sta song_pos | |
| 232 | + | lda #>song_data | |
| 233 | + | sta song_pos_hi | |
| 234 | + | | |
| 235 | + | lda #0 | |
| 236 | + | sta frame_count | |
| 237 | + | sta beat_count | |
| 238 | + | sta song_beat | |
| 239 | + | sta border_flash | |
| 240 | + | sta game_over | |
| 241 | + | | |
| 242 | + | jsr display_progress | |
| 243 | + | rts | |
| 244 | + | | |
| 245 | + | ; ---------------------------------------------------------------------------- | |
| 246 | + | ; Advance Song - Increment beat and update progress | |
| 247 | + | ; ---------------------------------------------------------------------------- | |
| 248 | + | | |
| 249 | + | advance_song: | |
| 250 | + | inc beat_count | |
| 251 | + | inc song_beat | |
| 252 | + | | |
| 253 | + | ; Check if song has ended | |
| 254 | + | lda song_beat | |
| 255 | + | cmp #SONG_LENGTH | |
| 256 | + | bcc song_continues | |
| 257 | + | | |
| 258 | + | ; Song loops for now (Unit 11 will add proper end) | |
| 259 | + | lda #0 | |
| 260 | + | sta song_beat | |
| 261 | + | sta beat_count | |
| 262 | + | lda #<song_data | |
| 263 | + | sta song_pos | |
| 264 | + | lda #>song_data | |
| 265 | + | sta song_pos_hi | |
| 266 | + | | |
| 267 | + | song_continues: | |
| 268 | + | jsr display_progress | |
| 269 | + | rts | |
| 270 | + | | |
| 271 | + | ; ---------------------------------------------------------------------------- | |
| 272 | + | ; Display Progress - Show song progress bar | |
| 273 | + | ; ---------------------------------------------------------------------------- | |
| 274 | + | | |
| 275 | + | display_progress: | |
| 276 | + | ; Calculate progress: (song_beat * PROGRESS_WIDTH) / SONG_LENGTH | |
| 277 | + | ; For 64-beat song with 16-char bar: song_beat / 4 | |
| 278 | + | | |
| 279 | + | lda song_beat | |
| 280 | + | lsr ; Divide by 4 | |
| 281 | + | lsr | |
| 282 | + | sta temp_progress | |
| 283 | + | | |
| 284 | + | ; Draw filled portion | |
| 285 | + | ldx #0 | |
| 286 | + | lda temp_progress | |
| 287 | + | beq draw_empty_progress | |
| 288 | + | | |
| 289 | + | draw_full_progress: | |
| 290 | + | lda #CHAR_BAR_FULL | |
| 291 | + | sta SCREEN + (PROGRESS_ROW * 40) + 12,x | |
| 292 | + | lda #PROGRESS_COL | |
| 293 | + | sta COLRAM + (PROGRESS_ROW * 40) + 12,x | |
| 294 | + | inx | |
| 295 | + | cpx temp_progress | |
| 296 | + | bne draw_full_progress | |
| 297 | + | | |
| 298 | + | draw_empty_progress: | |
| 299 | + | cpx #PROGRESS_WIDTH | |
| 300 | + | beq progress_done | |
| 301 | + | lda #CHAR_BAR_EMPTY | |
| 302 | + | sta SCREEN + (PROGRESS_ROW * 40) + 12,x | |
| 303 | + | lda #11 ; Dark grey | |
| 304 | + | sta COLRAM + (PROGRESS_ROW * 40) + 12,x | |
| 305 | + | inx | |
| 306 | + | jmp draw_empty_progress | |
| 307 | + | | |
| 308 | + | progress_done: | |
| 309 | + | rts | |
| 310 | + | | |
| 311 | + | temp_progress: !byte 0 | |
| 231 | 312 | | |
| 232 | 313 | ; ---------------------------------------------------------------------------- | |
| 233 | 314 | ; Copy Character Set from ROM to RAM | |
| ... | |||
| 298 | 379 | | |
| 299 | 380 | lda #%00000000 | |
| 300 | 381 | sta CHARSET + (CHAR_TRACK * 8) + 0 | |
| 301 | - | lda #%00000000 | |
| 302 | 382 | sta CHARSET + (CHAR_TRACK * 8) + 1 | |
| 303 | - | lda #%00000000 | |
| 304 | 383 | sta CHARSET + (CHAR_TRACK * 8) + 2 | |
| 305 | 384 | lda #%11111111 | |
| 306 | 385 | sta CHARSET + (CHAR_TRACK * 8) + 3 | |
| 307 | - | lda #%11111111 | |
| 308 | 386 | sta CHARSET + (CHAR_TRACK * 8) + 4 | |
| 309 | 387 | lda #%00000000 | |
| 310 | 388 | sta CHARSET + (CHAR_TRACK * 8) + 5 | |
| 311 | - | lda #%00000000 | |
| 312 | 389 | sta CHARSET + (CHAR_TRACK * 8) + 6 | |
| 313 | - | lda #%00000000 | |
| 314 | 390 | sta CHARSET + (CHAR_TRACK * 8) + 7 | |
| 315 | 391 | | |
| 316 | 392 | lda #%01100110 | |
| ... | |||
| 380 | 456 | init_notes_loop: | |
| 381 | 457 | sta note_track,x | |
| 382 | 458 | sta note_col,x | |
| 383 | - | sta note_freq,x ; Also clear note frequencies | |
| 459 | + | sta note_freq,x | |
| 384 | 460 | dex | |
| 385 | 461 | bpl init_notes_loop | |
| 386 | 462 | rts | |
| 387 | 463 | | |
| 388 | 464 | ; ---------------------------------------------------------------------------- | |
| 389 | - | ; Check Spawn Note - Now reads 3-byte song entries | |
| 465 | + | ; Check Spawn Note | |
| 390 | 466 | ; ---------------------------------------------------------------------------- | |
| 391 | 467 | | |
| 392 | 468 | check_spawn_note: | |
| ... | |||
| 395 | 471 | spawn_check_loop: | |
| 396 | 472 | lda (song_pos),y | |
| 397 | 473 | cmp #$FF | |
| 398 | - | beq spawn_restart_song | |
| 474 | + | beq spawn_done ; Don't auto-restart here | |
| 399 | 475 | | |
| 400 | 476 | cmp beat_count | |
| 401 | 477 | beq spawn_match | |
| ... | |||
| 405 | 481 | | |
| 406 | 482 | spawn_match: | |
| 407 | 483 | iny | |
| 408 | - | lda (song_pos),y ; Track number | |
| 484 | + | lda (song_pos),y | |
| 409 | 485 | sta temp_track | |
| 410 | 486 | iny | |
| 411 | - | lda (song_pos),y ; Note frequency | |
| 487 | + | lda (song_pos),y | |
| 412 | 488 | pha | |
| 413 | 489 | lda temp_track | |
| 414 | 490 | jsr spawn_note_with_freq | |
| 415 | - | pla ; Clean up stack | |
| 491 | + | pla | |
| 416 | 492 | dey | |
| 417 | 493 | dey | |
| 418 | 494 | | |
| 419 | 495 | spawn_advance: | |
| 420 | 496 | lda song_pos | |
| 421 | 497 | clc | |
| 422 | - | adc #3 ; 3 bytes per entry now | |
| 498 | + | adc #3 | |
| 423 | 499 | sta song_pos | |
| 424 | 500 | lda song_pos_hi | |
| 425 | 501 | adc #0 | |
| ... | |||
| 427 | 503 | jmp spawn_check_loop | |
| 428 | 504 | | |
| 429 | 505 | spawn_done: | |
| 430 | - | rts | |
| 431 | - | | |
| 432 | - | spawn_restart_song: | |
| 433 | - | lda #<song_data | |
| 434 | - | sta song_pos | |
| 435 | - | lda #>song_data | |
| 436 | - | sta song_pos_hi | |
| 437 | - | lda #0 | |
| 438 | - | sta beat_count | |
| 439 | 506 | rts | |
| 440 | 507 | | |
| 441 | 508 | ; ---------------------------------------------------------------------------- | |
| 442 | 509 | ; Spawn Note With Frequency | |
| 443 | - | ; Input: A = track, stack has frequency | |
| 444 | 510 | ; ---------------------------------------------------------------------------- | |
| 445 | 511 | | |
| 446 | 512 | spawn_note_with_freq: | |
| ... | |||
| 461 | 527 | lda #NOTE_SPAWN_COL | |
| 462 | 528 | sta note_col,x | |
| 463 | 529 | | |
| 464 | - | ; Get frequency from stack (caller pushed it) | |
| 465 | 530 | tsx | |
| 466 | - | lda $0103,x ; Get frequency from stack | |
| 531 | + | lda $0103,x | |
| 467 | 532 | sta note_freq,x | |
| 468 | 533 | | |
| 469 | 534 | jsr draw_note | |
| ... | |||
| 613 | 678 | | |
| 614 | 679 | draw_full_bars: | |
| 615 | 680 | lda #CHAR_BAR_FULL | |
| 616 | - | sta SCREEN + (HEALTH_ROW * 40) + 16,x | |
| 681 | + | sta SCREEN + (HEALTH_ROW * 40) + 12,x | |
| 617 | 682 | lda #HEALTH_COL | |
| 618 | - | sta COLRAM + (HEALTH_ROW * 40) + 16,x | |
| 683 | + | sta COLRAM + (HEALTH_ROW * 40) + 12,x | |
| 619 | 684 | inx | |
| 620 | 685 | cpx temp_health | |
| 621 | 686 | bne draw_full_bars | |
| ... | |||
| 624 | 689 | cpx #8 | |
| 625 | 690 | beq health_done | |
| 626 | 691 | lda #CHAR_BAR_EMPTY | |
| 627 | - | sta SCREEN + (HEALTH_ROW * 40) + 16,x | |
| 692 | + | sta SCREEN + (HEALTH_ROW * 40) + 12,x | |
| 628 | 693 | lda #11 | |
| 629 | - | sta COLRAM + (HEALTH_ROW * 40) + 16,x | |
| 694 | + | sta COLRAM + (HEALTH_ROW * 40) + 12,x | |
| 630 | 695 | inx | |
| 631 | 696 | jmp draw_empty_bars | |
| 632 | 697 | | |
| ... | |||
| 874 | 939 | cpx #38 | |
| 875 | 940 | bne draw_t1 | |
| 876 | 941 | | |
| 877 | - | lda #CHAR_TRACK | |
| 878 | 942 | ldx #0 | |
| 879 | 943 | draw_t2: | |
| 880 | 944 | sta SCREEN + (TRACK2_ROW * 40),x | |
| ... | |||
| 882 | 946 | cpx #38 | |
| 883 | 947 | bne draw_t2 | |
| 884 | 948 | | |
| 885 | - | lda #CHAR_TRACK | |
| 886 | 949 | ldx #0 | |
| 887 | 950 | draw_t3: | |
| 888 | 951 | sta SCREEN + (TRACK3_ROW * 40),x | |
| ... | |||
| 972 | 1035 | draw_health_label: | |
| 973 | 1036 | lda health_label,x | |
| 974 | 1037 | beq draw_health_label_done | |
| 975 | - | sta SCREEN + (HEALTH_ROW * 40) + 8,x | |
| 1038 | + | sta SCREEN + (HEALTH_ROW * 40) + 4,x | |
| 976 | 1039 | lda #5 | |
| 977 | - | sta COLRAM + (HEALTH_ROW * 40) + 8,x | |
| 1040 | + | sta COLRAM + (HEALTH_ROW * 40) + 4,x | |
| 978 | 1041 | inx | |
| 979 | 1042 | bne draw_health_label | |
| 980 | 1043 | draw_health_label_done: | |
| 1044 | + | | |
| 1045 | + | ldx #0 | |
| 1046 | + | draw_progress_label: | |
| 1047 | + | lda progress_label,x | |
| 1048 | + | beq draw_progress_label_done | |
| 1049 | + | sta SCREEN + (PROGRESS_ROW * 40) + 4,x | |
| 1050 | + | lda #3 | |
| 1051 | + | sta COLRAM + (PROGRESS_ROW * 40) + 4,x | |
| 1052 | + | inx | |
| 1053 | + | bne draw_progress_label | |
| 1054 | + | draw_progress_label_done: | |
| 981 | 1055 | | |
| 982 | 1056 | lda #$1A | |
| 983 | 1057 | sta SCREEN + (TRACK1_ROW * 40) | |
| ... | |||
| 1010 | 1084 | | |
| 1011 | 1085 | health_label: | |
| 1012 | 1086 | !scr "health:" | |
| 1087 | + | !byte 0 | |
| 1088 | + | | |
| 1089 | + | progress_label: | |
| 1090 | + | !scr "song:" | |
| 1013 | 1091 | !byte 0 | |
| 1014 | 1092 | | |
| 1015 | 1093 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 1190 | 1268 | rts | |
| 1191 | 1269 | | |
| 1192 | 1270 | ; ---------------------------------------------------------------------------- | |
| 1193 | - | ; Check Hit - Now stores note frequency for playback | |
| 1271 | + | ; Check Hit | |
| 1194 | 1272 | ; ---------------------------------------------------------------------------- | |
| 1195 | 1273 | | |
| 1196 | 1274 | check_hit: | |
| ... | |||
| 1209 | 1287 | cmp #HIT_ZONE_MAX+1 | |
| 1210 | 1288 | bcs check_hit_next | |
| 1211 | 1289 | | |
| 1212 | - | ; Store note frequency for sound playback | |
| 1213 | 1290 | lda note_freq,x | |
| 1214 | 1291 | sta hit_note_freq | |
| 1215 | 1292 | | |
| 1293 | + | lda note_col,x | |
| 1216 | 1294 | cmp #HIT_ZONE_CENTRE | |
| 1217 | 1295 | bcc hit_good | |
| 1218 | 1296 | cmp #HIT_ZONE_CENTRE+2 | |
| ... | |||
| 1487 | 1565 | | |
| 1488 | 1566 | ; ============================================================================ | |
| 1489 | 1567 | ; SONG DATA | |
| 1490 | - | ; ============================================================================ | |
| 1491 | - | ; Format: beat, track, note_freq_hi | |
| 1492 | - | ; | |
| 1493 | - | ; Note frequency table (high byte only for simplicity): | |
| 1494 | - | ; C3=$11 D3=$13 E3=$16 F3=$17 G3=$1A A3=$1D B3=$21 | |
| 1495 | - | ; C4=$23 D4=$27 E4=$2C F4=$2F G4=$35 A4=$3B B4=$42 | |
| 1496 | - | ; C5=$47 D5=$4F E5=$58 F5=$5E G5=$6A A5=$77 B5=$85 | |
| 1497 | - | ; | |
| 1498 | - | ; Track 1 (Z) = high notes, sawtooth | |
| 1499 | - | ; Track 2 (X) = mid notes, pulse | |
| 1500 | - | ; Track 3 (C) = low notes, triangle | |
| 1501 | 1568 | ; ============================================================================ | |
| 1502 | 1569 | | |
| 1503 | 1570 | song_data: | |
| 1504 | - | ; Bar 1 - Opening phrase | |
| 1505 | - | !byte 0, 1, $47 ; C5 - high | |
| 1506 | - | !byte 2, 2, $2C ; E4 - mid | |
| 1507 | - | !byte 4, 3, $11 ; C3 - low | |
| 1571 | + | ; Bar 1 | |
| 1572 | + | !byte 0, 1, $47 | |
| 1573 | + | !byte 2, 2, $2C | |
| 1574 | + | !byte 4, 3, $11 | |
| 1508 | 1575 | | |
| 1509 | - | ; Bar 2 - Descending | |
| 1510 | - | !byte 8, 1, $3B ; A4 | |
| 1511 | - | !byte 10, 2, $27 ; D4 | |
| 1512 | - | !byte 12, 3, $13 ; D3 | |
| 1576 | + | ; Bar 2 | |
| 1577 | + | !byte 8, 1, $3B | |
| 1578 | + | !byte 10, 2, $27 | |
| 1579 | + | !byte 12, 3, $13 | |
| 1513 | 1580 | | |
| 1514 | - | ; Bar 3 - Building | |
| 1515 | - | !byte 16, 1, $35 ; G4 | |
| 1516 | - | !byte 17, 2, $2C ; E4 | |
| 1517 | - | !byte 18, 1, $3B ; A4 | |
| 1518 | - | !byte 20, 3, $16 ; E3 | |
| 1581 | + | ; Bar 3 | |
| 1582 | + | !byte 16, 1, $35 | |
| 1583 | + | !byte 17, 2, $2C | |
| 1584 | + | !byte 18, 1, $3B | |
| 1585 | + | !byte 20, 3, $16 | |
| 1519 | 1586 | | |
| 1520 | - | ; Bar 4 - Resolution | |
| 1521 | - | !byte 24, 1, $47 ; C5 | |
| 1522 | - | !byte 26, 2, $35 ; G4 | |
| 1523 | - | !byte 28, 3, $11 ; C3 | |
| 1587 | + | ; Bar 4 | |
| 1588 | + | !byte 24, 1, $47 | |
| 1589 | + | !byte 26, 2, $35 | |
| 1590 | + | !byte 28, 3, $11 | |
| 1524 | 1591 | | |
| 1525 | - | ; Bar 5 - New phrase | |
| 1526 | - | !byte 32, 2, $2F ; F4 | |
| 1527 | - | !byte 34, 1, $4F ; D5 | |
| 1528 | - | !byte 36, 3, $17 ; F3 | |
| 1592 | + | ; Bar 5 | |
| 1593 | + | !byte 32, 2, $2F | |
| 1594 | + | !byte 34, 1, $4F | |
| 1595 | + | !byte 36, 3, $17 | |
| 1529 | 1596 | | |
| 1530 | - | ; Bar 6 - Variation | |
| 1531 | - | !byte 40, 1, $58 ; E5 | |
| 1532 | - | !byte 42, 2, $2C ; E4 | |
| 1533 | - | !byte 44, 3, $11 ; C3 | |
| 1534 | - | !byte 46, 2, $27 ; D4 | |
| 1597 | + | ; Bar 6 | |
| 1598 | + | !byte 40, 1, $58 | |
| 1599 | + | !byte 42, 2, $2C | |
| 1600 | + | !byte 44, 3, $11 | |
| 1601 | + | !byte 46, 2, $27 | |
| 1535 | 1602 | | |
| 1536 | - | ; Bar 7 - Climax approach | |
| 1537 | - | !byte 48, 1, $6A ; G5 | |
| 1538 | - | !byte 49, 2, $35 ; G4 | |
| 1539 | - | !byte 50, 1, $58 ; E5 | |
| 1540 | - | !byte 52, 3, $1A ; G3 | |
| 1541 | - | !byte 54, 2, $2F ; F4 | |
| 1603 | + | ; Bar 7 | |
| 1604 | + | !byte 48, 1, $6A | |
| 1605 | + | !byte 49, 2, $35 | |
| 1606 | + | !byte 50, 1, $58 | |
| 1607 | + | !byte 52, 3, $1A | |
| 1608 | + | !byte 54, 2, $2F | |
| 1542 | 1609 | | |
| 1543 | - | ; Bar 8 - Resolution/Loop point | |
| 1544 | - | !byte 56, 1, $47 ; C5 | |
| 1545 | - | !byte 58, 2, $2C ; E4 | |
| 1546 | - | !byte 60, 3, $11 ; C3 | |
| 1547 | - | !byte 62, 1, $35 ; G4 | |
| 1610 | + | ; Bar 8 | |
| 1611 | + | !byte 56, 1, $47 | |
| 1612 | + | !byte 58, 2, $2C | |
| 1613 | + | !byte 60, 3, $11 | |
| 1614 | + | !byte 62, 1, $35 | |
| 1548 | 1615 | | |
| 1549 | - | !byte $FF ; End of song | |
| 1616 | + | !byte $FF | |
| 1550 | 1617 | | |
| 1551 | 1618 | ; ---------------------------------------------------------------------------- | |
| 1552 | 1619 | ; Note Arrays | |
| ... | |||
| 1559 | 1626 | !fill MAX_NOTES, 0 | |
| 1560 | 1627 | | |
| 1561 | 1628 | note_freq: | |
| 1562 | - | !fill MAX_NOTES, 0 ; Note frequency for each active note | |
| 1629 | + | !fill MAX_NOTES, 0 | |
| 1563 | 1630 | | |
| 1564 | 1631 | ; ---------------------------------------------------------------------------- | |
| 1565 | 1632 | ; Game Variables |