moe-bius/tsfm_speccy_player/player.asm
2025-08-14 19:33:16 +07:00

826 lines
27 KiB
NASM

; if this code looks like HLL vomit, you're pretty close
; i used index registers since speed is not critical, it's a music compo player after all ;)
include "opmfile.inc"
module player
MAX_CHANNELS equ 16
MAX_STACK_DEPTH equ 4
; channel structures format
struct channel_stack_t
ptr dw 0
frames_to_play dw 0
ends
struct channel_struct_t
page db 0 ; base page with stream data
ptr dw 0 ; current pointer
frames_to_play dw -1 ; used for stack popping
delay dw 1
reload dw 1
stack_pos db 0 ; stack offset
stack block channel_stack_t*MAX_STACK_DEPTH, 0 ; stack
; reg cache
reg_extch3_fhi block 3, 0 ; extch3 block/fnum-high reg
reg_fhi db 0 ; block/fnum-high reg
reserved block 2, 0
ends
struct player_struct_t
ch3_ofs_chip0 dw 0
ch3_ofs_chip1 dw 0
chip_idx db 0 ; current chip active
channel_idx db 0
end_of_frame db 0
do_next_op db 0
ssg_r7 block 2, 0
ends
; instantinate structures
align 256
player_channels:
channel_struct_t 0, 0 ; TODO: fill start offsets here
channel_struct_t 0, 0
channel_struct_t 0, 0
channel_struct_t 0, 0
channel_struct_t 2, music_p0_ch4
channel_struct_t 2, music_p0_ch5
channel_struct_t 2, music_p0_ch6
channel_struct_t 2, music_p0_ch7
channel_struct_t 0, 0
channel_struct_t 0, 0
channel_struct_t 0, 0
channel_struct_t 0, 0
channel_struct_t 2, music_p0_ch12
channel_struct_t 2, music_p0_ch13
channel_struct_t 2, music_p0_ch14
channel_struct_t 2, music_p0_ch15
player_struct player_struct_t player_channels+(channel_struct_t*(3+0)+channel_struct_t.reg_extch3_fhi), player_channels+(channel_struct_t*(3+8)+channel_struct_t.reg_extch3_fhi)
.i = 0
dup 16
display "channel ", /h, .i, " struct ofs: ", /h, player_channels+(channel_struct_t*.i)
.i = .i + 1
edup
; -----------------------------
; -----------------------------
; OPN register dump output
; in:
; BC = 0xFFFD
; DE = 0x00C0 ; 0xFFBF compensated for outi
; HL - registers in (reg:data) byte pairs, reg==0xFF - return
reg_out:
.loop:
ld b, d
ld a, [hl]
inc a ; test for 0xFF terminator
ret z
outi
ld b, e
outi
dup 4: nop : edup ; delay
jp .loop
; ------------------------
; pop from stack
; in: IX - channel context
; trashes A, DE
pop_stack:
dec [ix + channel_struct_t.stack_pos] ; --chctx->stack_pos;
ld l, [ix + channel_struct_t.stack_pos] : ld h, 0 ; hl = chctx->stack_pos;
add hl, hl ; *= 2
add hl, hl ; *= 4
ld de, channel_struct_t.stack
add hl, de
ld de, ix
add hl, de ; hl = st = chctx->stack + chctx->stack_pos;
ld e, [hl] : inc l
ld d, [hl] : inc l ; de = st->ptr
ld [ix + channel_struct_t.ptr], de ; chctx->ptr = st->ptr
ld e, [hl] : inc l
ld d, [hl] ; de = st->frames_to_play
ld [ix + channel_struct_t.frames_to_play], de ; chctx->frames_to_play = st->frames_to_play
ret
; ------------------------
; push to stack
; in: IX - channel context
; trashes A, DE
push_stack:
ld l, [ix + channel_struct_t.stack_pos] : ld h, 0 ; hl = chctx->stack_pos;
add hl, hl ; *= 2
add hl, hl ; *= 4
ld de, channel_struct_t.stack
add hl, de
ld de, ix
add hl, de ; hl = st = chctx->stack + chctx->stack_pos;
ld de, [ix + channel_struct_t.ptr]
ld [hl], e : inc l
ld [hl], d : inc l ; st->ptr = chctx->ptr
ld de, [ix + channel_struct_t.frames_to_play]
ld [hl], e : inc l
ld [hl], d : inc l ; st->frames_to_play = chctx->frames_to_play
inc [ix + channel_struct_t.stack_pos]
ret
; ------------------------
; set delay
; in: HL - stream ptr
; out: DE - delay, trashes A
set_delay:
ld a, [hl]
cp OPM_STREAM_DELAY_INT16
jp z, .int16
and 0xF0
cp OPM_STREAM_DELAY_INT12
jp z, .int12
cp OPM_STREAM_DELAY_SHORT
jp z, .short
ret
.int16:
inc hl
ldi de, [hl]
ret
.int12:
ldi a, [hl] : and 0x0F : ld d, a
ldi e, [hl]
ret
.short:
ldi a, [hl] : and 0x0F : inc a : ld e, a : ld d, 0
ret
; ------------------------------------------
; parse AY channel stream
; HL - stream data, IX- channel context, IY - register buffer, CF - do next op
parse_ay_channel_stream:
ld b, [hl]
; if ((*(data) & 0x80) == OPM_AYTONE_REGS) {
ld a, b : and 0x80 : cp OPM_AYTONE_REGS
jp nz, .not_regs
; volume and period low
; opn_write_reg(chip_index, 8 + ch, (mask & OPM_AYTONE_CMD00_VOLUME_MASK));
inc hl
ld a, [player_struct.channel_idx]
add 8
ldi [iy], a
ld a, b : and OPM_AYTONE_CMD00_VOLUME_MASK
ldi [iy], a
; if (mask & OPM_AYTONE_CMD00_PERIOD_LOW) opn_write_reg(chip_index, 0 + (ch<<1), *data++);
bit OPM_AYTONE_CMD00_PERIOD_LOW_BIT, b
jp z, 1f
ld a, [player_struct.channel_idx]
add a
ldi [iy], a
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYTONE_CMD00_EOF) endOfFrame = true;
bit OPM_AYTONE_CMD00_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_regs:
; if ((*(data) & 0xC0) == OPM_AYTONE_PERIOD) {
ld a, b : and 0xC0 : cp OPM_AYTONE_PERIOD
jp nz, .not_period
; period low/high
; opn_write_reg(chip_index, 1 + (ch<<1), (mask & OPM_AYTONE_CMD80_PERIOD_HIGH));
inc hl
ld a, [player_struct.channel_idx]
add a
add 1
ldi [iy], a
exa
ld a, b : and OPM_AYTONE_CMD80_PERIOD_HIGH
ldi [iy], a
exa
; if (mask & OPM_AYTONE_CMD80_PERIOD_LOW) opn_write_reg(chip_index, 0 + (ch << 1), *data++);
bit OPM_AYTONE_CMD80_PERIOD_LOW_BIT, b
jp z, 1f
dec a
ldi [iy], a
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYTONE_CMD00_EOF) endOfFrame = true;
bit OPM_AYTONE_CMD80_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_period:
; if ((*(data) & 0xF8) == OPM_AYTONE_MASK) {
ld a, b : and 0xF8 : cp OPM_AYTONE_MASK
jp nz, .not_mask
inc hl
push de, hl, ix
; ctx->ssg_r7[chip_index] &= ~(((1 << 3) | (1 << 0)) << ch);
ld a, [player_struct.chip_idx] : ld e, a : ld d, 0
ld ix, player_struct.ssg_r7
add ix, de ; ix = ctx->ssg_r7[chip_index]
ld a, [player_struct.channel_idx] : ld e, a
ld hl, .mask_channel
add hl, de
ld a, [ix] : and [hl] : exa ; a = ctx->ssg_r7[chip_index] &= ~(((1 << 3) | (1 << 0)) << ch);
sla e : sla e
ld a, b : and 3 : add e : ld e, a
ld hl, .mask_lookup
add hl, de
exa : or [hl] : ld [ix], a ; ctx->ssg_r7[chip_index] |= (mask_lookup[mask & 3] << ch);
pop ix, hl, de
; if (mask & OPM_AYTONE_MASK_EOF) endOfFrame = true;
bit OPM_AYTONE_MASK_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.mask_lookup:
.p = 0
dup 3
db ((0<<3)|(0<<0)) << .p, ((0<<3)|(1<<0)) << .p, ((1<<3)|(0<<0)) << .p, ((1<<3)|(1<<0)) << .p
.p = .p + 1
edup
.mask_channel:
.p = 0
dup 3
db ~(((1<<3)|(1<<0)) << .p)
.p = .p + 1
edup
.not_mask:
.done:
and a ; clear carry
ret
; parse AY envelope/noise stream
; HL - stream data, IX- channel context, IY - register buffer, CF - do next op
parse_ay_envnoise_stream:
ld b, [hl]
; if ((*(data) & 0x80) == OPM_AYENV_REGS) {
ld a, b : and 0x80 : cp OPM_AYENV_REGS
jp nz, .not_regs
; opn_write_reg(chip_index, 6, (mask & OPM_AYENV_CMD00_NOISE_MASK));
inc hl
ldi [iy], 6
ld a, b : and OPM_AYENV_CMD00_NOISE_MASK
ldi [iy], a
; if (mask & OPM_AYENV_CMD00_PERIOD_LOW) opn_write_reg(chip_index, 11, *data++);
bit OPM_AYENV_CMD00_PERIOD_LOW_BIT, b
jp z, 1f
ldi [iy], 11
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYENV_CMD00_EOF) endOfFrame = true;
bit OPM_AYENV_CMD00_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_regs:
; if ((*(data) & 0xC0) == OPM_AYENV_ENVTYPE) {
ld a, b : and 0xC0 : cp OPM_AYENV_ENVTYPE
jp nz, .not_envtype
; opn_write_reg(chip_index, 13, (mask & OPM_AYENV_CMD80_ENV_TYPE));
inc hl
ldi [iy], 13
ld a, b : and OPM_AYENV_CMD80_ENV_TYPE
ldi [iy], a
; if (mask & OPM_AYENV_CMD80_PERIOD_LOW) opn_write_reg(chip_index, 11, *data++);
bit OPM_AYENV_CMD80_PERIOD_LOW_BIT, b
jp z, 1f
ldi [iy], 11
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYENV_CMD80_EOF) endOfFrame = true;
bit OPM_AYENV_CMD80_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_envtype:
; if ((*(data) & 0xF8) == OPM_AYENV_PERIOD_FULL) {
ld a, b : and 0xF8 : cp OPM_AYENV_PERIOD_FULL
jp nz, .not_period
inc hl
; if (mask & OPM_AYENV_CMDF0_PERIOD_LOW) opn_write_reg(chip_index, 11, *data++);
bit OPM_AYENV_CMDF0_PERIOD_LOW_BIT, b
jp z, 1f
ldi [iy], 11
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYENV_CMDF0_PERIOD_HIGH) opn_write_reg(chip_index, 12, *data++);
bit OPM_AYENV_CMDF0_PERIOD_HIGH_BIT, b
jp z, 1f
ldi [iy], 12
ldi a, [hl]
ldi [iy], a
1:
; if (mask & OPM_AYENV_CMDF0_EOF) endOfFrame = true;
bit OPM_AYENV_CMDF0_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_period:
and a ; clear carry
ret
; parse FM control stream
; HL - stream data, IX- channel context, IY - register buffer, CF - do next op
parse_fm_control_stream:
ld b, [hl]
; if ((*(data) & 0xE0) == OPM_CTRL_TIMER_CSM) {
ld a, b : and 0xE0 : cp OPM_CTRL_TIMER_CSM
jp nz, .not_timer_csm
inc hl
;if (mask & OPM_CTRL_CMD80_REG25) opn_write_reg(chip_index, 0x25, *data++);
bit OPM_CTRL_CMD80_REG25_BIT, b
jp z, 1f
ldi [iy], 0x25 : ldi a, [hl] : ldi [iy], a
1:
;if (mask & OPM_CTRL_CMD80_REG24) opn_write_reg(chip_index, 0x24, *data++);
bit OPM_CTRL_CMD80_REG24_BIT, b
jp z, 1f
ldi [iy], 0x24 : ldi a, [hl] : ldi [iy], a
1:
;if (mask & OPM_CTRL_CMD80_REG27) opn_write_reg(chip_index, 0x27, *data++);
bit OPM_CTRL_CMD80_REG27_BIT, b
jp z, 1f
ldi [iy], 0x27 : ldi a, [hl] : ldi [iy], a
1:
;if (mask & OPM_CTRL_CMD80_REG22) opn_write_reg(chip_index, 0x22, *data++);
bit OPM_CTRL_CMD80_REG25_BIT, b
jp z, 1f
ldi [iy], 0x22 : ldi a, [hl] : ldi [iy], a
1:
;if (mask & OPM_CTRL_CMD80_EOF) endOfFrame = true;
bit OPM_CTRL_CMD80_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_timer_csm:
; if ((*(data) & 0x80) == OPM_CTRL_EXTCH3) {
ld a, b : and 0x80 : cp OPM_CTRL_EXTCH3
jp nz, .not_extch3
inc hl
; extract extch3 offset
push hl
ld a, [player_struct.chip_idx] : add a : ld e, a : ld d, 0
ld hl, player_struct.ch3_ofs_chip0 : add hl, de
ld e, [hl] : inc hl : ld d, [hl] ; de - channel 3 extch3 block
pop hl
; if (mask & OPM_CTRL_EXTCH3_OP1_HIGH) ctx->extch3_block[chip_index][0] = *data++;
; if (mask & OPM_CTRL_EXTCH3_OP1_LOW) {
; opn_write_reg(chip_index, 0xAD, ctx->extch3_block[chip_index][0]);
; opn_write_reg(chip_index, 0xA9, *data++);
; }
bit OPM_CTRL_EXTCH3_OP1_HIGH_BIT, b
jp z, 1f
ld a, [hl] : ld [de], a : inc hl
1:
bit OPM_CTRL_EXTCH3_OP1_LOW_BIT, b
jp z, 1f
ldi [iy], 0xAD : ld a, [de] : ldi [iy], a
ldi [iy], 0xA9 : ldi a, [hl] : ldi [iy], a
1:
inc e
; if (mask & OPM_CTRL_EXTCH3_OP2_HIGH) ctx->extch3_block[chip_index][1] = *data++;
; if (mask & OPM_CTRL_EXTCH3_OP2_LOW) {
; opn_write_reg(chip_index, 0xAC, ctx->extch3_block[chip_index][1]);
; opn_write_reg(chip_index, 0xA8, *data++);
; }
bit OPM_CTRL_EXTCH3_OP2_HIGH_BIT, b
jp z, 1f
ld a, [hl] : ld [de], a : inc hl
1:
bit OPM_CTRL_EXTCH3_OP2_LOW_BIT, b
jp z, 1f
ldi [iy], 0xAC : ld a, [de] : ldi [iy], a
ldi [iy], 0xA8 : ldi a, [hl] : ldi [iy], a
1:
inc e
; if (mask & OPM_CTRL_EXTCH3_OP3_HIGH) ctx->extch3_block[chip_index][2] = *data++;
; if (mask & OPM_CTRL_EXTCH3_OP3_LOW) {
; opn_write_reg(chip_index, 0xAE, ctx->extch3_block[chip_index][2]);
; opn_write_reg(chip_index, 0xAA, *data++);
; }
bit OPM_CTRL_EXTCH3_OP3_HIGH_BIT, b
jp z, 1f
ld a, [hl] : ld [de], a : inc hl
1:
bit OPM_CTRL_EXTCH3_OP3_LOW_BIT, b
jp z, 1f
ldi [iy], 0xAE : ld a, [de] : ldi [iy], a
ldi [iy], 0xAA : ldi a, [hl] : ldi [iy], a
1:
; if (mask & OPM_CTRL_EXTCH3_EOF) endOfFrame = true;
bit OPM_CTRL_EXTCH3_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_extch3:
and a ; clear carry
ret
; parse FM channel stream
; HL - stream data, IX- channel context, IY - register buffer, CF - do next op
parse_fm_channel_stream:
ld b, [hl]
; if ((*(data) & 0xC0) == OPM_FM_ADSR) {
ld a, b : and 0xC0 : cp OPM_FM_ADSR
jp nz, .not_adsr
inc hl
; int regbase = (ch & 3) + ((mask & OPM_FM_CMD00_OP_MASK) >> 2);
ld a, [player_struct.channel_idx] : ld c, a
ld a, b : and OPM_FM_CMD00_OP_MASK : rrca : rrca
or c : ld c, a
;if (mask & OPM_FM_CMD00_REG50) opn_write_reg(chip_index, 0x50 + regbase, *data++);
bit OPM_FM_CMD00_REG50_BIT, b
jp z, 1f
ld a, 0x50 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD00_REG60) opn_write_reg(chip_index, 0x60 + regbase, *data++);
bit OPM_FM_CMD00_REG60_BIT, b
jp z, 1f
ld a, 0x60 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD00_REG70) opn_write_reg(chip_index, 0x70 + regbase, *data++);
bit OPM_FM_CMD00_REG70_BIT, b
jp z, 1f
ld a, 0x70 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD00_REG80) opn_write_reg(chip_index, 0x80 + regbase, *data++);
bit OPM_FM_CMD00_REG80_BIT, b
jp z, 1f
ld a, 0x80 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
scf
ret
.not_adsr:
; if ((*(data) & 0xC0) == OPM_FM_MUL_TL_EG) {
ld a, b : and 0xC0 : cp OPM_FM_MUL_TL_EG
jp nz, .not_mul_tl_eg
; multplier\TL\SSG-EG
inc hl
; int regbase = (ch & 3) + ((mask & OPM_FM_CMD40_OP_MASK) >> 2);
ld a, [player_struct.channel_idx] : ld c, a
ld a, b : and OPM_FM_CMD40_OP_MASK : rrca : rrca
or c : ld c, a
;if (mask & OPM_FM_CMD40_REG30) opn_write_reg(chip_index, 0x30 + regbase, *data++);
bit OPM_FM_CMD40_REG30_BIT, b
jp z, 1f
ld a, 0x30 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD40_REG40) opn_write_reg(chip_index, 0x40 + regbase, *data++);
bit OPM_FM_CMD40_REG40_BIT, b
jp z, 1f
ld a, 0x40 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD40_REG90) opn_write_reg(chip_index, 0x90 + regbase, *data++);
bit OPM_FM_CMD40_REG90_BIT, b
jp z, 1f
ld a, 0x90 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
;if (mask & OPM_FM_CMD40_EOF) endOfFrame = true;
bit OPM_FM_CMD40_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_mul_tl_eg:
; if ((*(data) & 0xE0) == OPM_FM_FREQ_FB_PAN) {
ld a, b : and 0xE0 : cp OPM_FM_FREQ_FB_PAN
jp nz, .not_freq_fb_pan
inc hl
ld a, [player_struct.channel_idx] : ld c, a
; if (mask & OPM_FM_CMD80_REGA4) chctx->block = *data++;
bit OPM_FM_CMD80_REGA4_BIT, b
jp z, 1f
ldi a, [hl] : ld [ix + channel_struct_t.reg_fhi], a
1:
; if (mask & OPM_FM_CMD80_REGA0) {
; opn_write_reg(chip_index, 0xA4 + ch, chctx->block);
; opn_write_reg(chip_index, 0xA0 + ch, *data++);
; }
bit OPM_FM_CMD80_REGA0_BIT, b
jp z, 1f
ld a, 0xA4 : add c : ldi [iy], a
ld a, [ix + channel_struct_t.reg_fhi] : ldi [iy], a
ld a, 0xA0 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
; if (mask & OPM_FM_CMD80_REGB0) opn_write_reg(chip_index, 0xB0 + ch, *data++);
bit OPM_FM_CMD80_REGB0_BIT, b
jp z, 1f
ld a, 0xb0 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
; if (mask & OPM_FM_CMD80_REGB4) opn_write_reg(chip_index, 0xB4 + ch, *data++);
bit OPM_FM_CMD80_REGB4_BIT, b
jp z, 1f
ld a, 0xb4 : add c : ldi [iy], a
ldi a, [hl] : ld [iy], a
1:
; if (mask & OPM_FM_CMD80_EOF) endOfFrame = true;
bit OPM_FM_CMD80_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_freq_fb_pan:
; if ((*(data) & 0xE0) == OPM_FM_KEY) {
ld a, b : and 0xE0 : cp OPM_FM_KEY
jp nz, .not_key
; opn_write_reg(chip_index, 0x28, ((mask & OPM_FM_CMDA0_OP_MASK) << 4) + ch);
ld a, [player_struct.channel_idx] : ld c, a
ld a, b : and OPM_FM_CMDA0_OP_MASK
add a, a : add a, a : add a, a : add a, a : add a, c
ldi [iy], 0x28 : ldi [iy], a
1:
; if (mask & OPM_FM_CMDA0_EOF) endOfFrame = true;
bit OPM_FM_CMDA0_EOF_BIT, b
jp z, 1f
ld a, b : ld [player_struct.end_of_frame], a
1:
scf
ret
.not_key:
and a ; clear carry
ret
; --------------------------------
; parse channel stream
; in: IX - stream struct, IY - register buffer, BC - stream parser procedure, A - channel index
parse_stream:
; endOfFrame = false;
xor a : ld [player_struct.end_of_frame], a
; if (--chctx->stream.delay == 0) {
ld de, [ix+channel_struct_t.delay]
dec de
ld [ix+channel_struct_t.delay], de
ld a, d
or e
ret nz
; save proc ptr
ld [.proc], bc
; load stream pointer
ld a, [ix+channel_struct_t.page]
ld bc, 0x7FFD
out (c), a
ld de, [ix+channel_struct_t.ptr]
exd ; hl = chctx->stream.ptr
.tok_loop:
ld a, [player_struct.end_of_frame] : and a : jp nz, .end_of_frame
; common tokens
ld a, [hl]
cp OPM_STREAM_END
jp z, .tok_end_of_stream
cp OPM_STREAM_END_FRAME
jp z, .tok_end_of_frame
; call stream parser proc
call 0 ; :grins:
.proc equ $-2
jp c, .tok_loop ; token handled
; handle common tokens
ld b, [hl]
; if ((*data & 0xF0) == OPM_STREAM_BACKREF) {
ld a, b : and 0xF0 : cp OPM_STREAM_BACKREF
jp nz, .not_backref
; back reference, nested call :)
; int distance = ((*(data + 0) & 0x0F) << 8) | (*(data + 1));
ld a, b : and 0x0F : ld d, a : inc hl
ldi e, [hl] ; de = distance
ldi a, [hl] ; int frames_to_play = *(data + 2); data += 3
ld [ix + channel_struct_t.ptr], hl ; chctx->stream.ptr = data + 3;
push af, de, hl
call push_stack
pop hl, de, af
and a : sbc hl, de ; data -= distance;
; chctx->stream.frames_to_play = frames_to_play; // hack?
ld e, a : ld d, 0 : ld [ix + channel_struct_t.frames_to_play], de
jp .tok_loop
.not_backref:
; then it's most likely an delay
call set_delay
ld [ix + channel_struct_t.reload], de
; fetch next token until it's end of frame
jp .tok_loop
.tok_end_of_stream:
ld de, -1
ld [ix + channel_struct_t.delay], de
jp .end_of_frame
.tok_end_of_frame:
inc hl
.end_of_frame:
; chctx->stream.delay = chctx->stream.reload;
ld de, [ix + channel_struct_t.reload]
ld [ix + channel_struct_t.delay], de
; // decrement samples to play counter
; if (--chctx->stream.samples_to_play == 0) {
push hl
ld hl, [ix + channel_struct_t.frames_to_play]
dec hl
ld [ix + channel_struct_t.frames_to_play], hl
ld a, h : or l
pop hl
jp nz, .not_pop
.pop_loop:
call pop_stack ; todo: kludge below, fixme
push hl
ld hl, [ix + channel_struct_t.frames_to_play]
dec hl
ld [ix + channel_struct_t.frames_to_play], hl
ld a, h : or l
pop hl
jp z, .pop_loop ; to parse nested backrefs
ret
.not_pop:
exd
ld [ix+channel_struct_t.ptr], de
ret
; -----------------------------
; -----------------------------
; play one tick!!!
; trashes all registers
play_tick:
ld iy, reg_buffer
; play AY only for now
; chip_index = 0;
xor a : ld [player_struct.chip_idx], a
; opmplay_parse_stream(ctx, ctx->channels + 4, 0, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 4)
ld bc, parse_ay_channel_stream
ld a, 0 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 5, 1, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 5)
ld bc, parse_ay_channel_stream
ld a, 1 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 6, 2, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 6)
ld bc, parse_ay_channel_stream
ld a, 2 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 7, 0, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 7)
ld bc, parse_ay_envnoise_stream
call parse_stream
ldi [iy], 7
ld a, [player_struct.ssg_r7 + 0]
ldi [iy], a
; terminate list
ldi [iy], -1
; chip_index = 1;
ld a, 1 : ld [player_struct.chip_idx], a
; opmplay_parse_stream(ctx, ctx->channels + 4, 0, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 12)
ld bc, parse_ay_channel_stream
ld a, 0 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 5, 1, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 13)
ld bc, parse_ay_channel_stream
ld a, 1 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 6, 2, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 14)
ld bc, parse_ay_channel_stream
ld a, 2 : ld [player_struct.channel_idx], a
call parse_stream
; opmplay_parse_stream(ctx, ctx->channels + 7, 0, opmplay_parse_ay_channel_stream);
ld ix, player_channels + (channel_struct_t * 15)
ld bc, parse_ay_envnoise_stream
call parse_stream
ldi [iy], 7
ld a, [player_struct.ssg_r7 + 1]
ldi [iy], a
; terminate list
ldi [iy], -1
ret
endmodule