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gbt_player_bank1.s
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; --------------------------------------------------------------
; --- ---
; --- ---
; --- GBT PLAYER v2.1.1 ---
; --- ---
; --- ---
; --- Copyright (C) 2009-2015 Antonio Niño Díaz ---
; --- All rights reserved. ---
; --------------------------------------------------------------
;
.NR10 = 0xFF10
.NR11 = 0xFF11
.NR12 = 0xFF12
.NR13 = 0xFF13
.NR14 = 0xFF14
.NR21 = 0xFF16
.NR22 = 0xFF17
.NR23 = 0xFF18
.NR24 = 0xFF19
.NR30 = 0xFF1A
.NR31 = 0xFF1B
.NR32 = 0xFF1C
.NR33 = 0xFF1D
.NR34 = 0xFF1E
.NR41 = 0xFF20
.NR42 = 0xFF21
.NR43 = 0xFF22
.NR44 = 0xFF23
.NR50 = 0xFF24
.NR51 = 0xFF25
.NR52 = 0xFF26
; -----------------------------------------------------------------------
; Disabled for a 32kb (non-banked) rom / Needed only for 64kb+ roms
;.area _CODE_1
.area _CODE
gbt_wave: ; 8 sounds
.DB 0xA5,0xD7,0xC9,0xE1,0xBC,0x9A,0x76,0x31,0x0C,0xBA,0xDE,0x60,0x1B,0xCA,0x03,0x93 ; random :P
.DB 0xF0,0xE1,0xD2,0xC3,0xB4,0xA5,0x96,0x87,0x78,0x69,0x5A,0x4B,0x3C,0x2D,0x1E,0x0F
.DB 0xFD,0xEC,0xDB,0xCA,0xB9,0xA8,0x97,0x86,0x79,0x68,0x57,0x46,0x35,0x24,0x13,0x02 ; little up-downs
.DB 0xDE,0xFE,0xDC,0xBA,0x9A,0xA9,0x87,0x77,0x88,0x87,0x65,0x56,0x54,0x32,0x10,0x12
.DB 0xAB,0xCD,0xEF,0xED,0xCB,0xA0,0x12,0x3E,0xDC,0xBA,0xBC,0xDE,0xFE,0xDC,0x32,0x10 ; triangular broken
.DB 0xFF,0xEE,0xDD,0xCC,0xBB,0xAA,0x99,0x88,0x77,0x66,0x55,0x44,0x33,0x22,0x11,0x00 ; triangular
.DB 0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00 ; square 50%
.DB 0x79,0xBC,0xDE,0xEF,0xFF,0xEE,0xDC,0xB9,0x75,0x43,0x21,0x10,0x00,0x11,0x23,0x45 ; sine
gbt_noise: ; 16 sounds
; 7 bit
.DB 0x5F,0x5B,0x4B,0x2F,0x3B,0x58,0x1F,0x0F
; 15 bit
.DB 0x90,0x80,0x70,0x50,0x00
.DB 0x67,0x63,0x53
gbt_frequencies:
.DW 44, 156, 262, 363, 457, 547, 631, 710, 786, 854, 923, 986
.DW 1046, 1102, 1155, 1205, 1253, 1297, 1339, 1379, 1417, 1452, 1486, 1517
.DW 1546, 1575, 1602, 1627, 1650, 1673, 1694, 1714, 1732, 1750, 1767, 1783
.DW 1798, 1812, 1825, 1837, 1849, 1860, 1871, 1881, 1890, 1899, 1907, 1915
.DW 1923, 1930, 1936, 1943, 1949, 1954, 1959, 1964, 1969, 1974, 1978, 1982
.DW 1985, 1988, 1992, 1995, 1998, 2001, 2004, 2006, 2009, 2011, 2013, 2015
; -----------------------------------------------------------------------
_gbt_get_freq_from_index: ; a = index, bc = returned freq
ld hl,#gbt_frequencies
ld c,a
ld b,#0
add hl,bc
add hl,bc
ld c,(hl)
inc hl
ld b,(hl)
ret
; -----------------------------------------------------------------------
; ------------------------------ Channel 1 ------------------------------
; -----------------------------------------------------------------------
gbt_channel_1_handle:: ; de = info
ld a,(gbt_channels_enabled)
and a,#0x01
jr nz,channel1_enabled$
; Channel is disabled. Increment pointer as needed
ld a,(de)
inc de
bit 7,a
jr nz,ch1_more_bytes$
bit 6,a
jr z,ch1_no_more_bytes_this_channel$
jr ch1_one_more_byte$
ch1_more_bytes$:
ld a,(de)
inc de
bit 7,a
jr z,ch1_no_more_bytes_this_channel$
ch1_one_more_byte$:
inc de
ch1_no_more_bytes_this_channel$:
ret
channel1_enabled$:
; Channel 1 is enabled
ld a,(de)
inc de
bit 7,a
jr nz,ch1_has_frequency$
; Not frequency
bit 6,a
jr nz,ch1_instr_effects$
; Set volume or NOP
bit 5,a
jr nz,ch1_just_set_volume$
; NOP
ret
ch1_just_set_volume$:
; Set volume
and a,#0x0F
swap a
ld (gbt_vol+0),a
jr refresh_channel1_regs$
ch1_instr_effects$:
; Set instrument and effect
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+0),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = effect
call gbt_channel_1_set_effect
jr refresh_channel1_regs$
ch1_has_frequency$:
; Has frequency
and a,#0x7F
ld (gbt_arpeggio_freq_index+0*3),a
; This destroys hl and a. Returns freq in bc
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+0*2+0),a
ld a,b
ld (gbt_freq+0*2+1),a ; Get frequency
ld a,(de)
inc de
bit 7,a
jr nz,ch1_freq_instr_and_effect$
; Freq + Instr + Volume
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+0),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = volume
swap a
ld (gbt_vol+0),a
jr refresh_channel1_regs$
ch1_freq_instr_and_effect$:
; Freq + Instr + Effect
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+0),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = effect
call gbt_channel_1_set_effect
;jr refresh_channel1_regs$
refresh_channel1_regs$:
; fall through!!!!!
; -----------------
channel1_refresh_registers:
xor a,a
ld (#.NR10),a
ld a,(gbt_instr+0)
ld (#.NR11),a
ld a,(gbt_vol+0)
ld (#.NR12),a
ld a,(gbt_freq+0*2+0)
ld (#.NR13),a
ld a,(gbt_freq+0*2+1)
or a,#0x80 ; start
ld (#.NR14),a
ret
; ------------------
channel1_update_effects: ; returns 1 in a if it is needed to update sound registers
; Cut note
; --------
ld a,(gbt_cut_note_tick+0)
ld hl,#gbt_ticks_elapsed
cp a,(hl)
jp nz,ch1_dont_cut$
dec a ; a = 0xFF
ld (gbt_cut_note_tick+0),a ; disable cut note
xor a,a ; vol = 0
ld (#.NR12),a
ld a,#0x80 ; start
ld (#.NR14),a
ch1_dont_cut$:
; Arpeggio
; --------
ld a,(gbt_arpeggio_enabled+0)
and a,a
ret z ; a is 0, return 0
; If enabled arpeggio, handle it
ld a,(gbt_arpeggio_tick+0)
and a,a
jr nz,ch1_not_tick_0$
; Tick 0 - Set original frequency
ld a,(gbt_arpeggio_freq_index+0*3+0)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+0*2+0),a
ld a,b
ld (gbt_freq+0*2+1),a ; Set frequency
ld a,#1
ld (gbt_arpeggio_tick+0),a
ret ; ret 1
ch1_not_tick_0$:
cp a,#1
jr nz,ch1_not_tick_1$
; Tick 1
ld a,(gbt_arpeggio_freq_index+0*3+1)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+0*2+0),a
ld a,b
ld (gbt_freq+0*2+1),a ; Set frequency
ld a,#2
ld (gbt_arpeggio_tick+0),a
dec a
ret ; ret 1
ch1_not_tick_1$:
; Tick 2
ld a,(gbt_arpeggio_freq_index+0*3+2)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+0*2+0),a
ld a,b
ld (gbt_freq+0*2+1),a ; Set frequency
xor a,a
ld (gbt_arpeggio_tick+0),a
inc a
ret ; ret 1
; -----------------
; returns a = 1 if needed to update registers, 0 if not
gbt_channel_1_set_effect: ; a = effect, de = pointer to data.
ld hl,#gbt_ch1_jump_table$
ld c,a
ld b,#0
add hl,bc
add hl,bc
ld a,(hl+)
ld h,(hl)
ld l,a
ld a,(de) ; load args
inc de
jp (hl)
gbt_ch1_jump_table$:
.DW gbt_ch1_pan$
.DW gbt_ch1_arpeggio$
.DW gbt_ch1_cut_note$
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_jump_pattern
.DW gbt_ch1234_jump_position
.DW gbt_ch1234_speed
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
gbt_ch1_pan$:
and a,#0x11
ld (gbt_pan+0),a
ld a,#1
ret ; ret 1
gbt_ch1_arpeggio$:
ld b,a ; b = params
ld hl,#gbt_arpeggio_freq_index+0*3
ld c,(hl) ; c = base index
inc hl
ld a,b
swap a
and a,#0x0F
add a,c
ld (hl+),a ; save first increment
ld a,b
and a,#0x0F
add a,c
ld (hl),a ; save second increment
ld a,#1
ld (gbt_arpeggio_enabled+0),a
ld (gbt_arpeggio_tick+0),a
ret ; ret 1
gbt_ch1_cut_note$:
ld (gbt_cut_note_tick+0),a
xor a,a ; ret 0
ret
; -----------------------------------------------------------------------
; ------------------------------ Channel 2 ------------------------------
; -----------------------------------------------------------------------
gbt_channel_2_handle:: ; de = info
ld a,(gbt_channels_enabled)
and a,#0x02
jr nz,channel2_enabled$
; Channel is disabled. Increment pointer as needed
ld a,(de)
inc de
bit 7,a
jr nz,ch2_more_bytes$
bit 6,a
jr z,ch2_no_more_bytes_this_channel$
jr ch2_one_more_byte$
ch2_more_bytes$:
ld a,(de)
inc de
bit 7,a
jr z,ch2_no_more_bytes_this_channel$
ch2_one_more_byte$:
inc de
ch2_no_more_bytes_this_channel$:
ret
channel2_enabled$:
; Channel 2 is enabled
ld a,(de)
inc de
bit 7,a
jr nz,ch2_has_frequency$
; Not frequency
bit 6,a
jr nz,ch2_instr_effects$
; Set volume or NOP
bit 5,a
jr nz,ch2_just_set_volume$
; NOP
ret
ch2_just_set_volume$:
; Set volume
and a,#0x0F
swap a
ld (gbt_vol+1),a
jr refresh_channel2_regs$
ch2_instr_effects$:
; Set instrument and effect
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+1),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = effect
call gbt_channel_2_set_effect
jr refresh_channel2_regs$
ch2_has_frequency$:
; Has frequency
and a,#0x7F
ld (gbt_arpeggio_freq_index+1*3),a
; This destroys hl and a. Returns freq in bc
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+1*2+0),a
ld a,b
ld (gbt_freq+1*2+1),a ; Get frequency
ld a,(de)
inc de
bit 7,a
jr nz,ch2_freq_instr_and_effect$
; Freq + Instr + Volume
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+1),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = volume
swap a
ld (gbt_vol+1),a
jr refresh_channel2_regs$
ch2_freq_instr_and_effect$:
; Freq + Instr + Effect
ld b,a ; save byte
and a,#0x30
sla a
sla a
ld (gbt_instr+1),a ; Instrument
ld a,b ; restore byte
and a,#0x0F ; a = effect
call gbt_channel_2_set_effect
;jr .refresh_channel2_regs
refresh_channel2_regs$:
; fall through!!!!!
; -----------------
channel2_refresh_registers:
ld a,(gbt_instr+1)
ld (#.NR21),a
ld a,(gbt_vol+1)
ld (#.NR22),a
ld a,(gbt_freq+1*2+0)
ld (#.NR23),a
ld a,(gbt_freq+1*2+1)
or a,#0x80 ; start
ld (#.NR24),a
ret
; ------------------
channel2_update_effects: ; returns 1 in a if it is needed to update sound registers
; Cut note
; --------
ld a,(gbt_cut_note_tick+1)
ld hl,#gbt_ticks_elapsed
cp a,(hl)
jp nz,ch2_dont_cut$
dec a ; a = 0xFF
ld (gbt_cut_note_tick+1),a ; disable cut note
xor a,a ; vol = 0
ld (#.NR22),a
ld a,#0x80 ; start
ld (#.NR24),a
ch2_dont_cut$:
; Arpeggio
; --------
ld a,(gbt_arpeggio_enabled+1)
and a,a
ret z ; a is 0, return 0
; If enabled arpeggio, handle it
ld a,(gbt_arpeggio_tick+1)
and a,a
jr nz,ch2_not_tick_0$
; Tick 0 - Set original frequency
ld a,(gbt_arpeggio_freq_index+1*3+0)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+1*2+0),a
ld a,b
ld (gbt_freq+1*2+1),a ; Set frequency
ld a,#1
ld (gbt_arpeggio_tick+1),a
ret ; ret 1
ch2_not_tick_0$:
cp a,#1
jr nz,ch2_not_tick_1$
; Tick 1
ld a,(gbt_arpeggio_freq_index+1*3+1)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+1*2+0),a
ld a,b
ld (gbt_freq+1*2+1),a ; Set frequency
ld a,#2
ld (gbt_arpeggio_tick+1),a
dec a
ret ; ret 1
ch2_not_tick_1$:
; Tick 2
ld a,(gbt_arpeggio_freq_index+1*3+2)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+1*2+0),a
ld a,b
ld (gbt_freq+1*2+1),a ; Set frequency
xor a,a
ld (gbt_arpeggio_tick+1),a
inc a
ret ; ret 1
; -----------------
; returns a = 1 if needed to update registers, 0 if not
gbt_channel_2_set_effect: ; a = effect, de = pointer to data
ld hl,#gbt_ch2_jump_table$
ld c,a
ld b,#0
add hl,bc
add hl,bc
ld a,(hl+)
ld h,(hl)
ld l,a
ld a,(de) ; load args
inc de
jp (hl)
gbt_ch2_jump_table$:
.DW gbt_ch2_pan$
.DW gbt_ch2_arpeggio$
.DW gbt_ch2_cut_note$
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_jump_pattern
.DW gbt_ch1234_jump_position
.DW gbt_ch1234_speed
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
.DW gbt_ch1234_nop
gbt_ch2_pan$:
and a,#0x22
ld (gbt_pan+1),a
ld a,#1
ret ; ret 1
gbt_ch2_arpeggio$:
ld b,a ; b = params
ld hl,#gbt_arpeggio_freq_index+1*3
ld c,(hl) ; c = base index
inc hl
ld a,b
swap a
and a,#0x0F
add a,c
ld (hl+),a ; save first increment
ld a,b
and a,#0x0F
add a,c
ld (hl),a ; save second increment
ld a,#1
ld (gbt_arpeggio_enabled+1),a
ld (gbt_arpeggio_tick+1),a
ret ; ret 1
gbt_ch2_cut_note$:
ld (gbt_cut_note_tick+1),a
xor a,a ; ret 0
ret
; -----------------------------------------------------------------------
; ------------------------------ Channel 3 ------------------------------
; -----------------------------------------------------------------------
gbt_channel_3_handle:: ; de = info
ld a,(gbt_channels_enabled)
and a,#0x04
jr nz,channel3_enabled$
; Channel is disabled. Increment pointer as needed
ld a,(de)
inc de
bit 7,a
jr nz,ch3_more_bytes$
bit 6,a
jr z,ch3_no_more_bytes_this_channel$
jr ch3_one_more_byte$
ch3_more_bytes$:
ld a,(de)
inc de
bit 7,a
jr z,ch3_no_more_bytes_this_channel$
ch3_one_more_byte$:
inc de
ch3_no_more_bytes_this_channel$:
ret
channel3_enabled$:
; Channel 3 is enabled
ld a,(de)
inc de
bit 7,a
jr nz,ch3_has_frequency$
; Not frequency
bit 6,a
jr nz,ch3_effects$
; Set volume or NOP
bit 5,a
jr nz,ch3_just_set_volume$
; NOP
ret
ch3_just_set_volume$:
; Set volume
and a,#0x0F
swap a
ld (gbt_vol+2),a
jr refresh_channel3_regs$
ch3_effects$:
; Set effect
and a,#0x0F ; a = effect
call gbt_channel_3_set_effect
and a,a
ret z ; if 0, don't refresh registers
jr refresh_channel3_regs$
ch3_has_frequency$:
; Has frequency
and a,#0x7F
ld (gbt_arpeggio_freq_index+2*3),a
; This destroys hl and a. Returns freq in bc
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+2*2+0),a
ld a,b
ld (gbt_freq+2*2+1),a ; Get frequency
ld a,(de)
inc de
bit 7,a
jr nz,ch3_freq_instr_and_effect$
; Freq + Instr + Volume
ld b,a ; save byte
and a,#0x0F
ld (gbt_instr+2),a ; Instrument
ld a,b ; restore byte
and a,#0x30 ; a = volume
sla a
ld (gbt_vol+2),a
jr refresh_channel3_regs$
ch3_freq_instr_and_effect$:
; Freq + Instr + Effect
ld b,a ; save byte
and a,#0x0F
ld (gbt_instr+2),a ; Instrument
ld a,b ; restore byte
and a,#0x70
swap a ; a = effect (only 0-7 allowed here)
call gbt_channel_3_set_effect
;jr .refresh_channel3_regs
refresh_channel3_regs$:
; fall through!!!!!
; -----------------
channel3_refresh_registers:
xor a,a
ld (#.NR30),a ; disable
ld a,(gbt_channel3_loaded_instrument)
ld b,a
ld a,(gbt_instr+2)
cp a,b
call nz,gbt_channel3_load_instrument ; a = instrument
ld a,#0x80
ld (#.NR30),a ; enable
xor a,a
ld (#.NR31),a
ld a,(gbt_vol+2)
ld (#.NR32),a
ld a,(gbt_freq+2*2+0)
ld (#.NR33),a
ld a,(gbt_freq+2*2+1)
or a,#0x80 ; start
ld (#.NR34),a
ret
; ------------------
gbt_channel3_load_instrument:
ld (gbt_channel3_loaded_instrument),a
swap a ; a = a * 16
ld c,a
ld b,#0
ld hl,#gbt_wave
add hl,bc
ld c,#0x30
ld b,#16
ch3_loop$:
ld a,(hl+)
ldh (c),a
inc c
dec b
jr nz,ch3_loop$
ret
; ------------------
channel3_update_effects: ; returns 1 in a if it is needed to update sound registers
; Cut note
; --------
ld a,(gbt_cut_note_tick+2)
ld hl,#gbt_ticks_elapsed
cp a,(hl)
jp nz,ch3_dont_cut$
dec a ; a = 0xFF
ld (gbt_cut_note_tick+2),a ; disable cut note
ld a,#0x80
ld (#.NR30),a ; enable
xor a,a ; vol = 0
ld (#.NR32),a
ld a,#0x80 ; start
ld (#.NR34),a
ch3_dont_cut$:
; Arpeggio
; --------
ld a,(gbt_arpeggio_enabled+2)
and a,a
ret z ; a is 0, return 0
; If enabled arpeggio, handle it
ld a,(gbt_arpeggio_tick+2)
and a,a
jr nz,ch3_not_tick_0$
; Tick 0 - Set original frequency
ld a,(gbt_arpeggio_freq_index+2*3+0)
call _gbt_get_freq_from_index
ld a,c
ld (gbt_freq+2*2+0),a
ld a,b
ld (gbt_freq+2*2+1),a ; Set frequency
ld a,#1
ld (gbt_arpeggio_tick+2),a
ret ; ret 1
ch3_not_tick_0$:
cp a,#1
jr nz,ch3_not_tick_1$
; Tick 1
ld a,(gbt_arpeggio_freq_index+2*3+1)