Game 1 Unit 7 of 64 1 hr learning time
Miss Handling
Notes that scroll past unhit trigger punishment. A harsh sound and red flash for failure.
11% of SID Symphony
Reward without risk means nothing. Now missed notes punish the player with harsh feedback.
This unit adds miss detection. When a note scrolls past the hit zone without being hit, it counts as a miss. The border flashes red. A harsh noise burst plays. The miss counter increments. Players will feel their failures.
Run It
Assemble and run:
acme -f cbm -o symphony.prg symphony.asm
The miss counter displays next to the score. Let a note scroll off screen and watch it climb. Notice the red flash and harsh sound - distinctly unpleasant compared to the satisfying hit feedback.
Detecting Misses
A miss happens when a note scrolls past column 0 without being hit. The update_notes routine already moves notes left each frame. Now it checks if they’ve gone too far:
; ----------------------------------------------------------------------------
; Update Notes - Now detects misses
; ----------------------------------------------------------------------------
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 ; Note passed hit zone - MISS!
jsr draw_note
jmp update_next
update_miss:
; Note fell through - record the miss
lda note_track,x
sta miss_track ; Save which track for flash
lda #0
sta note_track,x ; Deactivate note
jsr handle_miss ; Process the miss
update_next:
inx
cpx #MAX_NOTES
bne update_loop
rts
; ----------------------------------------------------------------------------
; Handle Miss - Negative feedback for missed notes
; ----------------------------------------------------------------------------
handle_miss:
; Increment miss counter
inc miss_count
; Play miss sound (harsh noise burst)
jsr play_miss_sound
; Red border flash
lda #MISS_COL
sta BORDER
lda #8 ; Flash for 8 frames
sta border_flash
; Update miss display
jsr display_misses
rts
The key change is the cmp #1 and bcc update_miss sequence. When a note’s column drops below 1, it’s past the hit zone - a miss. The handle_miss routine processes the failure: increment counter, play sound, flash border, update display.
The Miss Sound
Good feedback makes failure feel like failure. The SID’s noise waveform creates a harsh, discordant sound perfect for punishment:
; ----------------------------------------------------------------------------
; Miss Sound Settings
; ----------------------------------------------------------------------------
MISS_FREQ = $08 ; Low rumble
MISS_WAVE = $81 ; Noise waveform
MISS_AD = $00 ; Instant attack, no decay
MISS_SR = $90 ; High sustain, fast release
; ----------------------------------------------------------------------------
; Play Miss Sound - Harsh noise burst
; ----------------------------------------------------------------------------
play_miss_sound:
; Use voice 3 for miss sound (temporary override)
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 ; Gate on
sta SID_V3_CTRL
rts
The noise waveform ($81) generates random noise instead of a musical tone. Combined with a low frequency ($08), it creates a harsh rumble. The high sustain ($90) lets it ring out briefly before fading - long enough to feel the sting.
Why Noise Works
The SID has four waveforms:
| Waveform | Value | Character |
|---|---|---|
| Triangle | $11 | Soft, mellow |
| Sawtooth | $21 | Bright, buzzy |
| Pulse | $41 | Variable, classic |
| Noise | $81 | Harsh, random |
For hit sounds, musical waveforms reward success with pleasant tones. For misses, noise punishes failure with discord. The contrast makes hits feel better and misses feel worse.
Miss Counter Display
The miss counter uses simpler maths than the score - just two digits (0-99):
display_misses:
lda miss_count
; Tens digit
ldx #0
miss_div_10:
cmp #10
bcc miss_done_10
sec
sbc #10
inx
jmp miss_div_10
miss_done_10:
; X = tens, A = ones
pha ; Save ones
txa
ora #$30
sta SCREEN + 21 ; Tens digit
pla
ora #$30
sta SCREEN + 22 ; Ones digit
rtsRepeated subtraction by 10 extracts the tens digit. What remains is the ones digit. Simple division without hardware support.
The Complete Code
; ============================================================================
; SID SYMPHONY - Unit 7: Miss Handling
; ============================================================================
; Notes that scroll past unhit trigger negative feedback. A harsh noise burst
; and red flash punish mistakes. Miss count tracks failures.
;
; 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 ; High pitch
VOICE2_FREQ = $0E ; Mid pitch
VOICE3_FREQ = $07 ; Low pitch
VOICE_AD = $09 ; Attack=0, Decay=9
VOICE_SR = $00 ; Sustain=0, Release=0
PULSE_WIDTH = $08 ; 50% duty cycle
; Miss sound settings
MISS_FREQ = $08 ; Low rumble
MISS_WAVE = $81 ; Noise waveform
MISS_AD = $00 ; Instant attack, no decay
MISS_SR = $90 ; High sustain, fast release
; Visual Settings
BORDER_COL = 0 ; Black border
BG_COL = 0 ; Black background
TRACK1_NOTE_COL = 10 ; Light red
TRACK2_NOTE_COL = 13 ; Light green
TRACK3_NOTE_COL = 14 ; Light blue
TRACK_LINE_COL = 11 ; Dark grey
HIT_ZONE_COL = 7 ; Yellow
FLASH1_COL = 2 ; Red
FLASH2_COL = 5 ; Green
FLASH3_COL = 6 ; Blue
HIT_COL = 1 ; White - flash on successful hit
PERFECT_COL = 1 ; White - perfect hit border flash
GOOD_COL = 7 ; Yellow - good hit border flash
MISS_COL = 2 ; Red - miss border flash
; ============================================================================
; SCORING SETTINGS
; ============================================================================
PERFECT_SCORE = 100
GOOD_SCORE = 50
; ============================================================================
; HIT DETECTION SETTINGS
; ============================================================================
HIT_ZONE_MIN = 2
HIT_ZONE_MAX = 5
HIT_ZONE_CENTRE = 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
CIA1_PRA = $DC00
CIA1_PRB = $DC01
; Track positions
TRACK1_ROW = 8
TRACK2_ROW = 12
TRACK3_ROW = 16
; Hit zone
HIT_ZONE_COLUMN = 3
; Custom character codes
CHAR_NOTE = 128
CHAR_TRACK = 129
CHAR_HITZONE = 130
CHAR_SPACE = 32
; 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 ; Track of missed note (for flash)
; ----------------------------------------------------------------------------
; BASIC Stub
; ----------------------------------------------------------------------------
* = $0801
!byte $0C, $08
!byte $0A, $00
!byte $9E
!text "2064"
!byte $00
!byte $00, $00
; ----------------------------------------------------------------------------
; Main Program
; ----------------------------------------------------------------------------
* = $0810
start:
jsr copy_charset
jsr init_screen
jsr init_sid
jsr init_notes
jsr init_score
lda #<song_data
sta song_pos
lda #>song_data
sta song_pos_hi
lda #0
sta frame_count
sta beat_count
sta border_flash
main_loop:
lda #$FF
wait_raster:
cmp $D012
bne wait_raster
inc frame_count
lda frame_count
cmp #FRAMES_PER_BEAT
bcc no_new_beat
lda #0
sta frame_count
jsr check_spawn_note
inc beat_count
no_new_beat:
jsr update_notes
jsr reset_track_colours
jsr update_border_flash
jsr check_keys
jmp main_loop
; ----------------------------------------------------------------------------
; 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
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 1
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 2
lda #%11111111
sta CHARSET + (CHAR_TRACK * 8) + 3
lda #%11111111
sta CHARSET + (CHAR_TRACK * 8) + 4
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 5
lda #%00000000
sta CHARSET + (CHAR_TRACK * 8) + 6
lda #%00000000
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
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
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_restart_song
cmp beat_count
beq spawn_match
bcs spawn_done
jmp spawn_advance
spawn_match:
iny
lda (song_pos),y
jsr spawn_note
dey
spawn_advance:
lda song_pos
clc
adc #2
sta song_pos
lda song_pos_hi
adc #0
sta song_pos_hi
jmp spawn_check_loop
spawn_done:
rts
spawn_restart_song:
lda #<song_data
sta song_pos
lda #>song_data
sta song_pos_hi
lda #0
sta beat_count
rts
; ----------------------------------------------------------------------------
; Spawn Note
; ----------------------------------------------------------------------------
spawn_note:
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
jsr draw_note
rts
; ----------------------------------------------------------------------------
; Update Notes - Now detects misses
; ----------------------------------------------------------------------------
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 ; Note passed hit zone - MISS!
jsr draw_note
jmp update_next
update_miss:
; Note fell through - record the miss
lda note_track,x
sta miss_track ; Save which track for flash
lda #0
sta note_track,x ; Deactivate note
jsr handle_miss ; Process the miss
update_next:
inx
cpx #MAX_NOTES
bne update_loop
rts
; ----------------------------------------------------------------------------
; Handle Miss - Negative feedback for missed notes
; ----------------------------------------------------------------------------
handle_miss:
; Increment miss counter
inc miss_count
; Play miss sound (harsh noise burst)
jsr play_miss_sound
; Red border flash
lda #MISS_COL
sta BORDER
lda #8 ; Flash for 8 frames
sta border_flash
; Update miss display
jsr display_misses
rts
; ----------------------------------------------------------------------------
; Play Miss Sound - Harsh noise burst
; ----------------------------------------------------------------------------
play_miss_sound:
; Use voice 3 for miss sound (temporary override)
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 ; Gate on
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
lda #CHAR_TRACK
ldx #0
draw_t2:
sta SCREEN + (TRACK2_ROW * 40),x
inx
cpx #38
bne draw_t2
lda #CHAR_TRACK
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:
; Draw "SCORE:" label
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:
; Draw "MISS:" label
ldx #0
draw_miss_label:
lda miss_label,x
beq draw_miss_label_done
sta SCREEN + 15,x
lda #2 ; Red
sta COLRAM + 15,x
inx
bne draw_miss_label
draw_miss_label_done:
; Draw title
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:
; Track labels
lda #$1A ; Z
sta SCREEN + (TRACK1_ROW * 40)
lda #TRACK1_NOTE_COL
sta COLRAM + (TRACK1_ROW * 40)
lda #$18 ; X
sta SCREEN + (TRACK2_ROW * 40)
lda #TRACK2_NOTE_COL
sta COLRAM + (TRACK2_ROW * 40)
lda #$03 ; C
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
; ----------------------------------------------------------------------------
; 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 #$10
bne check_x_key
lda #1
sta key_pressed
jsr check_hit
bcc check_x_key
jsr play_voice1
jsr flash_track1_hit
jsr award_points
check_x_key:
lda #$FB
sta CIA1_PRA
lda CIA1_PRB
and #$80
bne check_c_key
lda #2
sta key_pressed
jsr check_hit
bcc check_c_key
jsr play_voice2
jsr flash_track2_hit
jsr award_points
check_c_key:
lda #$FB
sta CIA1_PRA
lda CIA1_PRB
and #$10
bne check_keys_done
lda #3
sta key_pressed
jsr check_hit
bcc check_keys_done
jsr play_voice3
jsr flash_track3_hit
jsr award_points
check_keys_done:
lda #$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
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
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
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 - Simple 2-digit display
; ----------------------------------------------------------------------------
display_misses:
lda miss_count
; Tens digit
ldx #0
miss_div_10:
cmp #10
bcc miss_done_10
sec
sbc #10
inx
jmp miss_div_10
miss_done_10:
; X = tens, A = ones
pha ; Save ones
txa
ora #$30
sta SCREEN + 21 ; Tens digit
pla
ora #$30
sta SCREEN + 22 ; Ones digit
lda #2 ; Red
sta COLRAM + 21
sta COLRAM + 22
rts
work_lo: !byte 0
work_hi: !byte 0
; ----------------------------------------------------------------------------
; Play Voices
; ----------------------------------------------------------------------------
play_voice1:
lda #VOICE1_WAVE
ora #$01
sta SID_V1_CTRL
rts
play_voice2:
lda #VOICE2_WAVE
ora #$01
sta SID_V2_CTRL
rts
play_voice3:
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:
!byte 0, 1
!byte 2, 2
!byte 4, 3
!byte 6, 1
!byte 8, 2
!byte 10, 3
!byte 12, 1
!byte 14, 2
!byte 16, 3
!byte 18, 1
!byte 20, 2
!byte 22, 3
!byte 24, 1
!byte 25, 2
!byte 26, 3
!byte 28, 1
!byte 29, 2
!byte 30, 3
!byte $FF
; ----------------------------------------------------------------------------
; Note Arrays
; ----------------------------------------------------------------------------
note_track:
!fill MAX_NOTES, 0
note_col:
!fill MAX_NOTES, 0
; ----------------------------------------------------------------------------
; Game Variables
; ----------------------------------------------------------------------------
score_lo: !byte 0
score_hi: !byte 0
miss_count: !byte 0
Try This: Harsher Miss Sound
Make misses more punishing:
MISS_FREQ = $20 ; Higher pitch (more grating)
MISS_SR = $F0 ; Longer sustainThe higher pitch cuts through more sharply. The longer sustain extends the discomfort.
Try This: Longer Flash
Extend the visual punishment:
; In handle_miss:
lda #16 ; Flash for 16 frames (double)
sta border_flashWhat You’ve Learnt
- Miss detection - Checking when notes scroll past the playable zone
- Noise waveform - Using $81 for harsh, non-musical sound
- Negative feedback - Making failure feel distinctly unpleasant
- Simple division - Repeated subtraction for display conversion
What’s Next
In Unit 8, we’ll add a health system. Misses will now cost lives. Too many failures and the game ends. Stakes create tension.
What Changed
Unit 6 → Unit 7
+136-69
| 1 | 1 | ; ============================================================================ | |
| 2 | - | ; SID SYMPHONY - Unit 6: Scoring and Feedback | |
| 2 | + | ; SID SYMPHONY - Unit 7: Miss Handling | |
| 3 | 3 | ; ============================================================================ | |
| 4 | - | ; Score points for hitting notes. Perfect timing (centre of hit zone) awards | |
| 5 | - | ; more points than good timing (edges). Visual feedback rewards accuracy. | |
| 4 | + | ; Notes that scroll past unhit trigger negative feedback. A harsh noise burst | |
| 5 | + | ; and red flash punish mistakes. Miss count tracks failures. | |
| 6 | 6 | ; | |
| 7 | 7 | ; Controls: Z = Track 1 (high), X = Track 2 (mid), C = Track 3 (low) | |
| 8 | 8 | ; ============================================================================ | |
| ... | |||
| 23 | 23 | VOICE_AD = $09 ; Attack=0, Decay=9 | |
| 24 | 24 | VOICE_SR = $00 ; Sustain=0, Release=0 | |
| 25 | 25 | PULSE_WIDTH = $08 ; 50% duty cycle | |
| 26 | + | | |
| 27 | + | ; Miss sound settings | |
| 28 | + | MISS_FREQ = $08 ; Low rumble | |
| 29 | + | MISS_WAVE = $81 ; Noise waveform | |
| 30 | + | MISS_AD = $00 ; Instant attack, no decay | |
| 31 | + | MISS_SR = $90 ; High sustain, fast release | |
| 26 | 32 | | |
| 27 | 33 | ; Visual Settings | |
| 28 | 34 | BORDER_COL = 0 ; Black border | |
| ... | |||
| 42 | 48 | HIT_COL = 1 ; White - flash on successful hit | |
| 43 | 49 | PERFECT_COL = 1 ; White - perfect hit border flash | |
| 44 | 50 | GOOD_COL = 7 ; Yellow - good hit border flash | |
| 51 | + | MISS_COL = 2 ; Red - miss border flash | |
| 45 | 52 | | |
| 46 | 53 | ; ============================================================================ | |
| 47 | 54 | ; SCORING SETTINGS | |
| 48 | 55 | ; ============================================================================ | |
| 49 | 56 | | |
| 50 | - | PERFECT_SCORE = 100 ; Points for perfect hit | |
| 51 | - | GOOD_SCORE = 50 ; Points for good hit | |
| 57 | + | PERFECT_SCORE = 100 | |
| 58 | + | GOOD_SCORE = 50 | |
| 52 | 59 | | |
| 53 | 60 | ; ============================================================================ | |
| 54 | 61 | ; HIT DETECTION SETTINGS | |
| 55 | 62 | ; ============================================================================ | |
| 56 | 63 | | |
| 57 | - | HIT_ZONE_MIN = 2 ; Left edge of hit zone | |
| 58 | - | HIT_ZONE_MAX = 5 ; Right edge of hit zone | |
| 59 | - | HIT_ZONE_CENTRE = 3 ; Perfect hit position (and 4) | |
| 64 | + | HIT_ZONE_MIN = 2 | |
| 65 | + | HIT_ZONE_MAX = 5 | |
| 66 | + | HIT_ZONE_CENTRE = 3 | |
| 60 | 67 | | |
| 61 | 68 | ; ============================================================================ | |
| 62 | 69 | ; MEMORY MAP | |
| 63 | 70 | ; ============================================================================ | |
| 64 | 71 | | |
| 65 | - | SCREEN = $0400 ; Screen memory | |
| 66 | - | COLRAM = $D800 ; Colour RAM | |
| 67 | - | BORDER = $D020 ; Border colour | |
| 68 | - | BGCOL = $D021 ; Background colour | |
| 69 | - | CHARPTR = $D018 ; Character memory pointer | |
| 72 | + | SCREEN = $0400 | |
| 73 | + | COLRAM = $D800 | |
| 74 | + | BORDER = $D020 | |
| 75 | + | BGCOL = $D021 | |
| 76 | + | CHARPTR = $D018 | |
| 70 | 77 | | |
| 71 | - | CHARSET = $3000 ; Custom character set location | |
| 78 | + | CHARSET = $3000 | |
| 72 | 79 | | |
| 73 | 80 | ; SID registers | |
| 74 | 81 | SID = $D400 | |
| ... | |||
| 131 | 138 | song_pos_hi = $05 | |
| 132 | 139 | temp_track = $06 | |
| 133 | 140 | key_pressed = $07 | |
| 134 | - | hit_quality = $08 ; 0=none, 1=good, 2=perfect | |
| 135 | - | border_flash = $09 ; Frames remaining for border flash | |
| 141 | + | hit_quality = $08 | |
| 142 | + | border_flash = $09 | |
| 143 | + | miss_track = $0A ; Track of missed note (for flash) | |
| 136 | 144 | | |
| 137 | 145 | ; ---------------------------------------------------------------------------- | |
| 138 | 146 | ; BASIC Stub | |
| ... | |||
| 244 | 252 | ; ---------------------------------------------------------------------------- | |
| 245 | 253 | | |
| 246 | 254 | define_custom_chars: | |
| 247 | - | ; Character 128: Note (filled chevron pointing left) | |
| 248 | 255 | lda #%00000110 | |
| 249 | 256 | sta CHARSET + (CHAR_NOTE * 8) + 0 | |
| 250 | 257 | lda #%00011110 | |
| ... | |||
| 262 | 269 | lda #%00000110 | |
| 263 | 270 | sta CHARSET + (CHAR_NOTE * 8) + 7 | |
| 264 | 271 | | |
| 265 | - | ; Character 129: Track line (centered horizontal line) | |
| 266 | 272 | lda #%00000000 | |
| 267 | 273 | sta CHARSET + (CHAR_TRACK * 8) + 0 | |
| 268 | 274 | lda #%00000000 | |
| ... | |||
| 280 | 286 | lda #%00000000 | |
| 281 | 287 | sta CHARSET + (CHAR_TRACK * 8) + 7 | |
| 282 | 288 | | |
| 283 | - | ; Character 130: Hit zone (vertical bars) | |
| 284 | 289 | lda #%01100110 | |
| 285 | 290 | sta CHARSET + (CHAR_HITZONE * 8) + 0 | |
| 286 | - | lda #%01100110 | |
| 287 | 291 | sta CHARSET + (CHAR_HITZONE * 8) + 1 | |
| 288 | - | lda #%01100110 | |
| 289 | 292 | sta CHARSET + (CHAR_HITZONE * 8) + 2 | |
| 290 | - | lda #%01100110 | |
| 291 | 293 | sta CHARSET + (CHAR_HITZONE * 8) + 3 | |
| 292 | - | lda #%01100110 | |
| 293 | 294 | sta CHARSET + (CHAR_HITZONE * 8) + 4 | |
| 294 | - | lda #%01100110 | |
| 295 | 295 | sta CHARSET + (CHAR_HITZONE * 8) + 5 | |
| 296 | - | lda #%01100110 | |
| 297 | 296 | sta CHARSET + (CHAR_HITZONE * 8) + 6 | |
| 298 | - | lda #%01100110 | |
| 299 | 297 | sta CHARSET + (CHAR_HITZONE * 8) + 7 | |
| 300 | 298 | | |
| 301 | 299 | rts | |
| ... | |||
| 308 | 306 | lda #0 | |
| 309 | 307 | sta score_lo | |
| 310 | 308 | sta score_hi | |
| 309 | + | sta miss_count | |
| 311 | 310 | jsr display_score | |
| 311 | + | jsr display_misses | |
| 312 | 312 | rts | |
| 313 | 313 | | |
| 314 | 314 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 396 | 396 | rts | |
| 397 | 397 | | |
| 398 | 398 | ; ---------------------------------------------------------------------------- | |
| 399 | - | ; Update Notes | |
| 399 | + | ; Update Notes - Now detects misses | |
| 400 | 400 | ; ---------------------------------------------------------------------------- | |
| 401 | 401 | | |
| 402 | 402 | update_notes: | |
| ... | |||
| 411 | 411 | dec note_col,x | |
| 412 | 412 | lda note_col,x | |
| 413 | 413 | cmp #1 | |
| 414 | - | bcc update_deactivate | |
| 414 | + | bcc update_miss ; Note passed hit zone - MISS! | |
| 415 | 415 | | |
| 416 | 416 | jsr draw_note | |
| 417 | 417 | jmp update_next | |
| 418 | 418 | | |
| 419 | - | update_deactivate: | |
| 419 | + | update_miss: | |
| 420 | + | ; Note fell through - record the miss | |
| 421 | + | lda note_track,x | |
| 422 | + | sta miss_track ; Save which track for flash | |
| 420 | 423 | lda #0 | |
| 421 | - | sta note_track,x | |
| 424 | + | sta note_track,x ; Deactivate note | |
| 425 | + | jsr handle_miss ; Process the miss | |
| 422 | 426 | | |
| 423 | 427 | update_next: | |
| 424 | 428 | inx | |
| 425 | 429 | cpx #MAX_NOTES | |
| 426 | 430 | bne update_loop | |
| 431 | + | rts | |
| 432 | + | | |
| 433 | + | ; ---------------------------------------------------------------------------- | |
| 434 | + | ; Handle Miss - Negative feedback for missed notes | |
| 435 | + | ; ---------------------------------------------------------------------------- | |
| 436 | + | | |
| 437 | + | handle_miss: | |
| 438 | + | ; Increment miss counter | |
| 439 | + | inc miss_count | |
| 440 | + | | |
| 441 | + | ; Play miss sound (harsh noise burst) | |
| 442 | + | jsr play_miss_sound | |
| 443 | + | | |
| 444 | + | ; Red border flash | |
| 445 | + | lda #MISS_COL | |
| 446 | + | sta BORDER | |
| 447 | + | lda #8 ; Flash for 8 frames | |
| 448 | + | sta border_flash | |
| 449 | + | | |
| 450 | + | ; Update miss display | |
| 451 | + | jsr display_misses | |
| 452 | + | | |
| 453 | + | rts | |
| 454 | + | | |
| 455 | + | ; ---------------------------------------------------------------------------- | |
| 456 | + | ; Play Miss Sound - Harsh noise burst | |
| 457 | + | ; ---------------------------------------------------------------------------- | |
| 458 | + | | |
| 459 | + | play_miss_sound: | |
| 460 | + | ; Use voice 3 for miss sound (temporary override) | |
| 461 | + | lda #0 | |
| 462 | + | sta SID_V3_FREQ_LO | |
| 463 | + | lda #MISS_FREQ | |
| 464 | + | sta SID_V3_FREQ_HI | |
| 465 | + | lda #MISS_AD | |
| 466 | + | sta SID_V3_AD | |
| 467 | + | lda #MISS_SR | |
| 468 | + | sta SID_V3_SR | |
| 469 | + | lda #MISS_WAVE | |
| 470 | + | ora #$01 ; Gate on | |
| 471 | + | sta SID_V3_CTRL | |
| 427 | 472 | rts | |
| 428 | 473 | | |
| 429 | 474 | ; ---------------------------------------------------------------------------- | |
| ... | |||
| 714 | 759 | lda score_label,x | |
| 715 | 760 | beq draw_score_label_done | |
| 716 | 761 | sta SCREEN + 1,x | |
| 717 | - | lda #1 ; White | |
| 762 | + | lda #1 | |
| 718 | 763 | sta COLRAM + 1,x | |
| 719 | 764 | inx | |
| 720 | 765 | bne draw_score_label | |
| 721 | 766 | draw_score_label_done: | |
| 767 | + | | |
| 768 | + | ; Draw "MISS:" label | |
| 769 | + | ldx #0 | |
| 770 | + | draw_miss_label: | |
| 771 | + | lda miss_label,x | |
| 772 | + | beq draw_miss_label_done | |
| 773 | + | sta SCREEN + 15,x | |
| 774 | + | lda #2 ; Red | |
| 775 | + | sta COLRAM + 15,x | |
| 776 | + | inx | |
| 777 | + | bne draw_miss_label | |
| 778 | + | draw_miss_label_done: | |
| 722 | 779 | | |
| 723 | 780 | ; Draw title | |
| 724 | 781 | ldx #0 | |
| ... | |||
| 752 | 809 | | |
| 753 | 810 | score_label: | |
| 754 | 811 | !scr "score:" | |
| 812 | + | !byte 0 | |
| 813 | + | | |
| 814 | + | miss_label: | |
| 815 | + | !scr "miss:" | |
| 755 | 816 | !byte 0 | |
| 756 | 817 | | |
| 757 | 818 | title_text: | |
| ... | |||
| 870 | 931 | ; ---------------------------------------------------------------------------- | |
| 871 | 932 | ; Update Border Flash | |
| 872 | 933 | ; ---------------------------------------------------------------------------- | |
| 873 | - | ; Decrements flash counter and resets border when done | |
| 874 | 934 | | |
| 875 | 935 | update_border_flash: | |
| 876 | 936 | lda border_flash | |
| 877 | 937 | beq flash_done | |
| 878 | 938 | dec border_flash | |
| 879 | 939 | bne flash_done | |
| 880 | - | ; Flash finished - reset border | |
| 881 | 940 | lda #BORDER_COL | |
| 882 | 941 | sta BORDER | |
| 883 | 942 | flash_done: | |
| 884 | 943 | rts | |
| 885 | 944 | | |
| 886 | 945 | ; ---------------------------------------------------------------------------- | |
| 887 | - | ; Check Keys - With hit detection and scoring | |
| 946 | + | ; Check Keys | |
| 888 | 947 | ; ---------------------------------------------------------------------------- | |
| 889 | 948 | | |
| 890 | 949 | check_keys: | |
| 891 | - | ; Check Z key (track 1) | |
| 892 | 950 | lda #$FD | |
| 893 | 951 | sta CIA1_PRA | |
| 894 | 952 | lda CIA1_PRB | |
| ... | |||
| 904 | 962 | jsr award_points | |
| 905 | 963 | | |
| 906 | 964 | check_x_key: | |
| 907 | - | ; Check X key (track 2) | |
| 908 | 965 | lda #$FB | |
| 909 | 966 | sta CIA1_PRA | |
| 910 | 967 | lda CIA1_PRB | |
| ... | |||
| 920 | 977 | jsr award_points | |
| 921 | 978 | | |
| 922 | 979 | check_c_key: | |
| 923 | - | ; Check C key (track 3) | |
| 924 | 980 | lda #$FB | |
| 925 | 981 | sta CIA1_PRA | |
| 926 | 982 | lda CIA1_PRB | |
| ... | |||
| 941 | 997 | rts | |
| 942 | 998 | | |
| 943 | 999 | ; ---------------------------------------------------------------------------- | |
| 944 | - | ; Check Hit - Find note and determine hit quality | |
| 1000 | + | ; Check Hit | |
| 945 | 1001 | ; ---------------------------------------------------------------------------- | |
| 946 | - | ; Input: key_pressed = track number (1-3) | |
| 947 | - | ; Output: Carry set if hit, hit_quality set (1=good, 2=perfect) | |
| 948 | - | ; Carry clear if no hit | |
| 949 | 1002 | | |
| 950 | 1003 | check_hit: | |
| 951 | 1004 | ldx #0 | |
| ... | |||
| 963 | 1016 | cmp #HIT_ZONE_MAX+1 | |
| 964 | 1017 | bcs check_hit_next | |
| 965 | 1018 | | |
| 966 | - | ; HIT! Determine quality based on position | |
| 967 | - | ; Centre columns (3-4) = perfect, edges (2, 5) = good | |
| 968 | 1019 | cmp #HIT_ZONE_CENTRE | |
| 969 | - | bcc hit_good ; Column 2 = good | |
| 1020 | + | bcc hit_good | |
| 970 | 1021 | cmp #HIT_ZONE_CENTRE+2 | |
| 971 | - | bcs hit_good ; Column 5 = good | |
| 1022 | + | bcs hit_good | |
| 972 | 1023 | | |
| 973 | - | ; Perfect hit (columns 3-4) | |
| 974 | 1024 | lda #2 | |
| 975 | 1025 | sta hit_quality | |
| 976 | 1026 | jmp hit_found | |
| 977 | 1027 | | |
| 978 | 1028 | hit_good: | |
| 979 | - | ; Good hit (columns 2 or 5) | |
| 980 | 1029 | lda #1 | |
| 981 | 1030 | sta hit_quality | |
| 982 | 1031 | | |
| ... | |||
| 998 | 1047 | rts | |
| 999 | 1048 | | |
| 1000 | 1049 | ; ---------------------------------------------------------------------------- | |
| 1001 | - | ; Award Points - Add score based on hit quality | |
| 1050 | + | ; Award Points | |
| 1002 | 1051 | ; ---------------------------------------------------------------------------- | |
| 1003 | 1052 | | |
| 1004 | 1053 | award_points: | |
| ... | |||
| 1006 | 1055 | cmp #2 | |
| 1007 | 1056 | beq award_perfect | |
| 1008 | 1057 | | |
| 1009 | - | ; Good hit - add 50 points | |
| 1010 | 1058 | lda score_lo | |
| 1011 | 1059 | clc | |
| 1012 | 1060 | adc #GOOD_SCORE | |
| ... | |||
| 1015 | 1063 | adc #0 | |
| 1016 | 1064 | sta score_hi | |
| 1017 | 1065 | | |
| 1018 | - | ; Yellow border flash for good | |
| 1019 | 1066 | lda #GOOD_COL | |
| 1020 | 1067 | sta BORDER | |
| 1021 | - | lda #4 ; Flash for 4 frames | |
| 1068 | + | lda #4 | |
| 1022 | 1069 | sta border_flash | |
| 1023 | 1070 | | |
| 1024 | 1071 | jmp award_done | |
| 1025 | 1072 | | |
| 1026 | 1073 | award_perfect: | |
| 1027 | - | ; Perfect hit - add 100 points | |
| 1028 | 1074 | lda score_lo | |
| 1029 | 1075 | clc | |
| 1030 | 1076 | adc #PERFECT_SCORE | |
| ... | |||
| 1033 | 1079 | adc #0 | |
| 1034 | 1080 | sta score_hi | |
| 1035 | 1081 | | |
| 1036 | - | ; White border flash for perfect | |
| 1037 | 1082 | lda #PERFECT_COL | |
| 1038 | 1083 | sta BORDER | |
| 1039 | - | lda #6 ; Flash for 6 frames | |
| 1084 | + | lda #6 | |
| 1040 | 1085 | sta border_flash | |
| 1041 | 1086 | | |
| 1042 | 1087 | award_done: | |
| ... | |||
| 1044 | 1089 | rts | |
| 1045 | 1090 | | |
| 1046 | 1091 | ; ---------------------------------------------------------------------------- | |
| 1047 | - | ; Display Score - Convert 16-bit score to decimal and show | |
| 1092 | + | ; Display Score | |
| 1048 | 1093 | ; ---------------------------------------------------------------------------- | |
| 1049 | 1094 | | |
| 1050 | 1095 | display_score: | |
| 1051 | - | ; Convert score to 5-digit decimal display | |
| 1052 | - | ; Uses simple repeated subtraction method | |
| 1053 | - | | |
| 1054 | - | ; Copy score to working area | |
| 1055 | 1096 | lda score_lo | |
| 1056 | 1097 | sta work_lo | |
| 1057 | 1098 | lda score_hi | |
| 1058 | 1099 | sta work_hi | |
| 1059 | 1100 | | |
| 1060 | - | ; Ten-thousands digit | |
| 1061 | 1101 | ldx #0 | |
| 1062 | 1102 | div_10000: | |
| 1063 | 1103 | lda work_lo | |
| ... | |||
| 1073 | 1113 | jmp div_10000 | |
| 1074 | 1114 | done_10000: | |
| 1075 | 1115 | txa | |
| 1076 | - | ora #$30 ; Convert to screen code | |
| 1116 | + | ora #$30 | |
| 1077 | 1117 | sta SCREEN + 8 | |
| 1078 | 1118 | | |
| 1079 | - | ; Thousands digit | |
| 1080 | 1119 | ldx #0 | |
| 1081 | 1120 | div_1000: | |
| 1082 | 1121 | lda work_lo | |
| ... | |||
| 1095 | 1134 | ora #$30 | |
| 1096 | 1135 | sta SCREEN + 9 | |
| 1097 | 1136 | | |
| 1098 | - | ; Hundreds digit | |
| 1099 | 1137 | ldx #0 | |
| 1100 | 1138 | div_100: | |
| 1101 | 1139 | lda work_lo | |
| ... | |||
| 1110 | 1148 | ora #$30 | |
| 1111 | 1149 | sta SCREEN + 10 | |
| 1112 | 1150 | | |
| 1113 | - | ; Tens digit | |
| 1114 | 1151 | ldx #0 | |
| 1115 | 1152 | div_10: | |
| 1116 | 1153 | lda work_lo | |
| ... | |||
| 1125 | 1162 | ora #$30 | |
| 1126 | 1163 | sta SCREEN + 11 | |
| 1127 | 1164 | | |
| 1128 | - | ; Ones digit | |
| 1129 | 1165 | lda work_lo | |
| 1130 | 1166 | ora #$30 | |
| 1131 | 1167 | sta SCREEN + 12 | |
| 1132 | 1168 | | |
| 1133 | - | ; Set score digit colours | |
| 1134 | - | lda #7 ; Yellow for score | |
| 1169 | + | lda #7 | |
| 1135 | 1170 | sta COLRAM + 8 | |
| 1136 | 1171 | sta COLRAM + 9 | |
| 1137 | 1172 | sta COLRAM + 10 | |
| ... | |||
| 1140 | 1175 | | |
| 1141 | 1176 | rts | |
| 1142 | 1177 | | |
| 1143 | - | ; Working variables for division | |
| 1178 | + | ; ---------------------------------------------------------------------------- | |
| 1179 | + | ; Display Misses - Simple 2-digit display | |
| 1180 | + | ; ---------------------------------------------------------------------------- | |
| 1181 | + | | |
| 1182 | + | display_misses: | |
| 1183 | + | lda miss_count | |
| 1184 | + | | |
| 1185 | + | ; Tens digit | |
| 1186 | + | ldx #0 | |
| 1187 | + | miss_div_10: | |
| 1188 | + | cmp #10 | |
| 1189 | + | bcc miss_done_10 | |
| 1190 | + | sec | |
| 1191 | + | sbc #10 | |
| 1192 | + | inx | |
| 1193 | + | jmp miss_div_10 | |
| 1194 | + | miss_done_10: | |
| 1195 | + | ; X = tens, A = ones | |
| 1196 | + | pha ; Save ones | |
| 1197 | + | txa | |
| 1198 | + | ora #$30 | |
| 1199 | + | sta SCREEN + 21 ; Tens digit | |
| 1200 | + | pla | |
| 1201 | + | ora #$30 | |
| 1202 | + | sta SCREEN + 22 ; Ones digit | |
| 1203 | + | | |
| 1204 | + | lda #2 ; Red | |
| 1205 | + | sta COLRAM + 21 | |
| 1206 | + | sta COLRAM + 22 | |
| 1207 | + | | |
| 1208 | + | rts | |
| 1209 | + | | |
| 1144 | 1210 | work_lo: !byte 0 | |
| 1145 | 1211 | work_hi: !byte 0 | |
| 1146 | 1212 | | |
| ... | |||
| 1246 | 1312 | !fill MAX_NOTES, 0 | |
| 1247 | 1313 | | |
| 1248 | 1314 | ; ---------------------------------------------------------------------------- | |
| 1249 | - | ; Score Variables | |
| 1315 | + | ; Game Variables | |
| 1250 | 1316 | ; ---------------------------------------------------------------------------- | |
| 1251 | 1317 | | |
| 1252 | 1318 | score_lo: !byte 0 | |
| 1253 | 1319 | score_hi: !byte 0 | |
| 1320 | + | miss_count: !byte 0 | |
| 1254 | 1321 | |