diff options
Diffstat (limited to 'audio.asm')
| -rw-r--r-- | audio.asm | 91 |
1 files changed, 54 insertions, 37 deletions
@@ -365,7 +365,7 @@ SECTION "Audio Engine 1", ROMX, BANK[AUDIO_1] PlayBattleMusic:: ; 0x90c6 xor a ld [wMusicHeaderPointer], a - ld [wd083], a + ld [wLowHealthAlarm], a dec a ld [wc0ee], a call PlaySound ; stop music @@ -455,63 +455,80 @@ Music_Cities1AlternateTempo:: ; 0x9b81 SECTION "Audio Engine 2", ROMX, BANK[AUDIO_2] -Func_2136e:: ; 2136e (8:536e) - ld a, [wd083] +Music_DoLowHealthAlarm:: ; 2136e (8:536e) + ld a, [wLowHealthAlarm] cp $ff - jr z, .asm_2139b - bit 7, a - ret z - and $7f - jr nz, .asm_21383 - call Func_213a7 - ld a, $1e - jr .asm_21395 + jr z, .disableAlarm + + bit 7, a ;alarm enabled? + ret z ;nope + + and $7f ;low 7 bits are the timer. + jr nz, .asm_21383 ;if timer > 0, play low tone. + + call .playToneHi + ld a, 30 ;keep this tone for 30 frames. + jr .asm_21395 ;reset the timer. + .asm_21383 - cp $14 - jr nz, .asm_2138a - call Func_213ac + cp 20 + jr nz, .asm_2138a ;if timer == 20, + call .playToneLo ;actually set the sound registers. + .asm_2138a ld a, $86 - ld [wc02a], a - ld a, [wd083] - and $7f + ld [wc02a], a ;disable sound channel? + ld a, [wLowHealthAlarm] + and $7f ;decrement alarm timer. dec a + .asm_21395 + ; reset the timer and enable flag. set 7, a - ld [wd083], a + ld [wLowHealthAlarm], a ret -.asm_2139b + +.disableAlarm xor a - ld [wd083], a - ld [wc02a], a - ld de, Unknown_213c4 ; $53c4 - jr asm_213af - -Func_213a7: ; 213a7 (8:53a7) - ld de, Unknown_213bc ; $53bc - jr asm_213af - -Func_213ac: ; 213ac (8:53ac) - ld de, Unknown_213c0 ; $53c0 -asm_213af: ; 213af (8:53af) - ld hl, $ff10 + ld [wLowHealthAlarm], a ;disable alarm + ld [wc02a], a ;re-enable sound channel? + ld de, .toneDataSilence + jr .playTone + +;update the sound registers to change the frequency. +;the tone set here stays until we change it. +.playToneHi + ld de, .toneDataHi + jr .playTone + +.playToneLo + ld de, .toneDataLo + +;update sound channel 1 to play the alarm, overriding all other sounds. +.playTone + ld hl, rNR10 ;channel 1 sound register ld c, $5 xor a -.asm_213b5 + +.copyLoop ld [hli], a ld a, [de] inc de dec c - jr nz, .asm_213b5 + jr nz, .copyLoop ret -Unknown_213bc: ; 213bc (8:53bc) +;bytes to write to sound channel 1 registers for health alarm. +;starting at FF11 (FF10 is always zeroed), so these bytes are: +;length, envelope, freq lo, freq hi +.toneDataHi db $A0,$E2,$50,$87 -Unknown_213c0: ; 213c0 (8:53c0) +.toneDataLo db $B0,$E2,$EE,$86 -Unknown_213c4: ; 213c4 (8:53c4) +;written to stop the alarm +.toneDataSilence db $00,$00,$00,$80 |