chiptune_player: split interrupt handler to own file
This commit is contained in:
Vince Weaver
parent
f0c93935e2
commit
21d183616e
|
|
@ -36,7 +36,8 @@
|
|||
;COUNT EQU $06
|
||||
;DELTA EQU $08
|
||||
|
||||
orgoff EQU $5E00 ; offset of first unpacked byte
|
||||
;UNPACK_BUFFER EQU $5E00 ; offset of first unpacked byte
|
||||
|
||||
|
||||
;======================
|
||||
; LZ4 decode
|
||||
|
|
@ -54,9 +55,9 @@ lz4_decode:
|
|||
adc LZ4_END+1
|
||||
sta LZ4_END+1
|
||||
|
||||
lda #>orgoff ; original unpacked data offset
|
||||
lda #>UNPACK_BUFFER ; original unpacked data offset
|
||||
sta LZ4_DST+1
|
||||
lda #<orgoff
|
||||
lda #<UNPACK_BUFFER
|
||||
sta LZ4_DST
|
||||
|
||||
unpmain:
|
||||
|
|
|
|||
|
|
@ -33,7 +33,7 @@ chiptune_player.o: chiptune_player.s \
|
|||
../asm_routines/mockingboard.s \
|
||||
../asm_routines/dos33_routines.s \
|
||||
../asm_routines/lz4_decode.s \
|
||||
rasterbars.s volume_bars.s \
|
||||
rasterbars.s volume_bars.s interrupt_handler.s \
|
||||
chip_title.inc zp.inc
|
||||
ca65 -o chiptune_player.o chiptune_player.s -l chiptune_player.lst
|
||||
|
||||
|
|
|
|||
|
|
@ -3,7 +3,7 @@
|
|||
.include "zp.inc"
|
||||
; program is ~4k, so from 0xc00 to 0x1C00
|
||||
LZ4_BUFFER EQU $1C00 ; $1C00 - $5C00, 16k for now
|
||||
CHUNK_BUFFER EQU $5E00 ; $5E00 - $9600, 14k, $3800
|
||||
UNPACK_BUFFER EQU $5E00 ; $5E00 - $9600, 14k, $3800
|
||||
; trying not to hit DOS at $9600
|
||||
; Reserve 3 chunks plus spare (14k)
|
||||
CHUNKSIZE EQU $3
|
||||
|
|
@ -126,9 +126,9 @@ mockingboard_found:
|
|||
jsr new_song
|
||||
|
||||
|
||||
lda #<CHUNK_BUFFER ; set input pointer
|
||||
lda #<UNPACK_BUFFER ; set input pointer
|
||||
sta INL
|
||||
lda #>CHUNK_BUFFER
|
||||
lda #>UNPACK_BUFFER
|
||||
sta INH
|
||||
|
||||
|
||||
|
|
@ -196,167 +196,8 @@ done_play:
|
|||
forever_loop:
|
||||
jmp forever_loop
|
||||
|
||||
;=============================
|
||||
;=============================
|
||||
; simple interrupt handler
|
||||
;=============================
|
||||
;=============================
|
||||
; On Apple II/6502 the interrupt handler jumps to address in 0xfffe
|
||||
; This is in the ROM, which saves the registers
|
||||
; on older IIe it saved A to $45 (which could mess with DISK II)
|
||||
; newer IIe doesn't do that.
|
||||
; It then calculates if it is a BRK or not (which trashes A)
|
||||
; Then it sets up the stack like an interrupt and calls 0x3fe
|
||||
|
||||
interrupt_handler:
|
||||
pha ; save A ; 3
|
||||
; tya
|
||||
; pha
|
||||
; txa
|
||||
; pha
|
||||
; Should we save X and Y too?
|
||||
|
||||
; inc $0404 ; debug
|
||||
|
||||
bit $C404 ; clear 6522 interrupt by reading T1C-L ; 4
|
||||
|
||||
|
||||
;============
|
||||
; 7
|
||||
;=====================
|
||||
; Update time counter
|
||||
;=====================
|
||||
|
||||
inc FRAME_COUNT ; 5
|
||||
lda FRAME_COUNT ; 3
|
||||
cmp #50 ; 3
|
||||
bne frame_good ; 3/2nt
|
||||
|
||||
lda #$0 ; 2
|
||||
sta FRAME_COUNT ; 3
|
||||
|
||||
update_second_ones:
|
||||
inc $7d0+17 ; 6
|
||||
inc $bd0+17 ; 6
|
||||
lda $bd0+17 ; 4
|
||||
cmp #$ba ; one past '9' ; 2
|
||||
bne frame_good ; 3/2nt
|
||||
lda #'0'+$80 ; 2
|
||||
sta $7d0+17 ; 4
|
||||
sta $bd0+17 ; 4
|
||||
update_second_tens:
|
||||
inc $7d0+16 ; 6
|
||||
inc $bd0+16 ; 6
|
||||
lda $bd0+16 ; 4
|
||||
cmp #$b6 ; 6 (for 60 seconds) ; 2
|
||||
bne frame_good ; 3/2nt
|
||||
lda #'0'+$80 ; 2
|
||||
sta $7d0+16 ; 4
|
||||
sta $bd0+16 ; 4
|
||||
update_minutes:
|
||||
inc $7d0+14 ; 6
|
||||
inc $bd0+14 ; 6
|
||||
; we don't handle > 9:59 songs yet
|
||||
|
||||
;=============
|
||||
; 90 worst
|
||||
|
||||
frame_good:
|
||||
|
||||
ldy MB_FRAME_DIFF ; get chunk offset ; 3
|
||||
|
||||
ldx #0 ; set up reg count ; 2
|
||||
|
||||
;=============
|
||||
; 5
|
||||
|
||||
mb_write_loop:
|
||||
lda (INL),y ; load register value ; 5
|
||||
|
||||
; if REG==1 and high bit set
|
||||
; then end of song
|
||||
|
||||
bpl mb_not_done ; 3/2nt
|
||||
cpx #1 ; 2
|
||||
bne mb_not_done ; 3/2nt
|
||||
|
||||
lda #1 ; set done playing ; 2
|
||||
sta DONE_PLAYING ; 3
|
||||
jmp done_interrupt ; 3
|
||||
|
||||
mb_not_done:
|
||||
|
||||
; special case R13. If it is 0xff, then don't update
|
||||
; otherwise might spuriously reset the envelope settings
|
||||
|
||||
cpx #13 ; 2
|
||||
bne mb_not_13 ; 3/2nt
|
||||
cmp #$ff ; 2
|
||||
beq skip_r13 ; 3/2nt
|
||||
|
||||
mb_not_13:
|
||||
sta MB_VALUE ; 3
|
||||
|
||||
; always write out all to zero page
|
||||
; we mostly care about vola/volb/volc so this wastes 11 bytes of RAM
|
||||
; code is simpler, and save on three cmp/branches per loop
|
||||
|
||||
and #$f ; 2
|
||||
sta REGISTER_DUMP,X ; 4
|
||||
|
||||
; INLINE this (could save 72 cycles)
|
||||
jsr write_ay_both ; assume 3 channel (not six) ; 6
|
||||
; so write same to both
|
||||
; left/right
|
||||
; 53
|
||||
|
||||
clc ; point to next interleaved ; 2
|
||||
lda INH ; page by adding $300 ; 3
|
||||
adc #CHUNKSIZE ; 2
|
||||
sta INH ; 3
|
||||
|
||||
inx ; point to next register ; 2
|
||||
cpx #14 ; if 14 we're done ; 2
|
||||
bmi mb_write_loop ; otherwise, loop ; 3/2nt
|
||||
;============
|
||||
; roughly 95?
|
||||
; *13= 1235?
|
||||
skip_r13:
|
||||
|
||||
inc MB_FRAME_DIFF ; increment offset ; 5
|
||||
bne reset_chunk ; if not zero, done ; 3/2nt
|
||||
|
||||
wraparound:
|
||||
|
||||
inc MB_CHUNK ; go to next chunk ; 5
|
||||
lda MB_CHUNK ; 3
|
||||
cmp #CHUNKSIZE ; have we reached end? ; 2
|
||||
bne reset_chunk ; 3/2nt
|
||||
lda #0 ; if so reset ; 2
|
||||
sta MB_CHUNK ; 3
|
||||
|
||||
; can't tail call as need to restore stack and rti
|
||||
jsr next_subsong ; and decompress next ; 6
|
||||
|
||||
|
||||
reset_chunk:
|
||||
lda MB_CHUNK ; reset input pointer ; 3
|
||||
clc ; to the beginning ; 2
|
||||
|
||||
adc #>CHUNK_BUFFER ; in proper chunk (1 of 3) ; 2
|
||||
sta INH ; 3
|
||||
|
||||
|
||||
;============
|
||||
; 18
|
||||
done_interrupt:
|
||||
pla ; restore a ; 4
|
||||
|
||||
rti ; return from interrupt ; 6
|
||||
|
||||
;============
|
||||
; typical
|
||||
; 1358 cycles
|
||||
|
||||
;=================
|
||||
; load a new song
|
||||
|
|
@ -526,13 +367,13 @@ bloop22:
|
|||
; DST: chunk_buffer+$2A00+(COPY_OFFSET*256)
|
||||
page_copy:
|
||||
clc ; 2
|
||||
lda #>(CHUNK_BUFFER+512) ; 3
|
||||
lda #>(UNPACK_BUFFER+512) ; 3
|
||||
adc COPY_OFFSET ; 3
|
||||
adc COPY_OFFSET ; 3
|
||||
adc COPY_OFFSET ; 3
|
||||
sta page_copy_loop+2 ; self modify ; 5
|
||||
|
||||
lda #>(CHUNK_BUFFER+$2A00) ; 2
|
||||
lda #>(UNPACK_BUFFER+$2A00) ; 2
|
||||
adc COPY_OFFSET ; 3
|
||||
sta page_copy_loop+5 ; self modify ; 5
|
||||
|
||||
|
|
@ -581,6 +422,7 @@ krw_file:
|
|||
.include "../asm_routines/lz4_decode.s"
|
||||
.include "rasterbars.s"
|
||||
.include "volume_bars.s"
|
||||
.include "interrupt_handler.s"
|
||||
|
||||
;=========
|
||||
; strings
|
||||
|
|
|
|||
|
|
@ -0,0 +1,158 @@
|
|||
;================================
|
||||
;================================
|
||||
; mockingboard interrupt handler
|
||||
;================================
|
||||
;================================
|
||||
; On Apple II/6502 the interrupt handler jumps to address in 0xfffe
|
||||
; This is in the ROM, which saves the registers
|
||||
; on older IIe it saved A to $45 (which could mess with DISK II)
|
||||
; newer IIe doesn't do that.
|
||||
; It then calculates if it is a BRK or not (which trashes A)
|
||||
; Then it sets up the stack like an interrupt and calls 0x3fe
|
||||
|
||||
interrupt_handler:
|
||||
pha ; save A ; 3
|
||||
; Should we save X and Y too?
|
||||
|
||||
; inc $0404 ; debug
|
||||
|
||||
bit $C404 ; clear 6522 interrupt by reading T1C-L ; 4
|
||||
|
||||
|
||||
;============
|
||||
; 7
|
||||
;=====================
|
||||
; Update time counter
|
||||
;=====================
|
||||
|
||||
inc FRAME_COUNT ; 5
|
||||
lda FRAME_COUNT ; 3
|
||||
cmp #50 ; 3
|
||||
bne frame_good ; 3/2nt
|
||||
|
||||
lda #$0 ; 2
|
||||
sta FRAME_COUNT ; 3
|
||||
|
||||
update_second_ones:
|
||||
inc $7d0+17 ; 6
|
||||
inc $bd0+17 ; 6
|
||||
lda $bd0+17 ; 4
|
||||
cmp #$ba ; one past '9' ; 2
|
||||
bne frame_good ; 3/2nt
|
||||
lda #'0'+$80 ; 2
|
||||
sta $7d0+17 ; 4
|
||||
sta $bd0+17 ; 4
|
||||
update_second_tens:
|
||||
inc $7d0+16 ; 6
|
||||
inc $bd0+16 ; 6
|
||||
lda $bd0+16 ; 4
|
||||
cmp #$b6 ; 6 (for 60 seconds) ; 2
|
||||
bne frame_good ; 3/2nt
|
||||
lda #'0'+$80 ; 2
|
||||
sta $7d0+16 ; 4
|
||||
sta $bd0+16 ; 4
|
||||
update_minutes:
|
||||
inc $7d0+14 ; 6
|
||||
inc $bd0+14 ; 6
|
||||
; we don't handle > 9:59 songs yet
|
||||
|
||||
;=============
|
||||
; 90 worst
|
||||
|
||||
frame_good:
|
||||
|
||||
ldy MB_FRAME_DIFF ; get chunk offset ; 3
|
||||
|
||||
ldx #0 ; set up reg count ; 2
|
||||
|
||||
;=============
|
||||
; 5
|
||||
|
||||
mb_write_loop:
|
||||
lda (INL),y ; load register value ; 5
|
||||
|
||||
; if REG==1 and high bit set
|
||||
; then end of song
|
||||
|
||||
bpl mb_not_done ; 3/2nt
|
||||
cpx #1 ; 2
|
||||
bne mb_not_done ; 3/2nt
|
||||
|
||||
lda #1 ; set done playing ; 2
|
||||
sta DONE_PLAYING ; 3
|
||||
jmp done_interrupt ; 3
|
||||
|
||||
mb_not_done:
|
||||
|
||||
; special case R13. If it is 0xff, then don't update
|
||||
; otherwise might spuriously reset the envelope settings
|
||||
|
||||
cpx #13 ; 2
|
||||
bne mb_not_13 ; 3/2nt
|
||||
cmp #$ff ; 2
|
||||
beq skip_r13 ; 3/2nt
|
||||
|
||||
mb_not_13:
|
||||
sta MB_VALUE ; 3
|
||||
|
||||
; always write out all to zero page
|
||||
; we mostly care about vola/volb/volc so this wastes 11 bytes of RAM
|
||||
; code is simpler, and save on three cmp/branches per loop
|
||||
|
||||
and #$f ; 2
|
||||
sta REGISTER_DUMP,X ; 4
|
||||
|
||||
; INLINE this (could save 72 cycles)
|
||||
jsr write_ay_both ; assume 3 channel (not six) ; 6
|
||||
; so write same to both
|
||||
; left/right
|
||||
; 53
|
||||
|
||||
clc ; point to next interleaved ; 2
|
||||
lda INH ; page by adding $300 ; 3
|
||||
adc #CHUNKSIZE ; 2
|
||||
sta INH ; 3
|
||||
|
||||
inx ; point to next register ; 2
|
||||
cpx #14 ; if 14 we're done ; 2
|
||||
bmi mb_write_loop ; otherwise, loop ; 3/2nt
|
||||
;============
|
||||
; roughly 95?
|
||||
; *13= 1235?
|
||||
skip_r13:
|
||||
|
||||
inc MB_FRAME_DIFF ; increment offset ; 5
|
||||
bne reset_chunk ; if not zero, done ; 3/2nt
|
||||
|
||||
wraparound:
|
||||
|
||||
inc MB_CHUNK ; go to next chunk ; 5
|
||||
lda MB_CHUNK ; 3
|
||||
cmp #CHUNKSIZE ; have we reached end? ; 2
|
||||
bne reset_chunk ; 3/2nt
|
||||
lda #0 ; if so reset ; 2
|
||||
sta MB_CHUNK ; 3
|
||||
|
||||
; can't tail call as need to restore stack and rti
|
||||
jsr next_subsong ; and decompress next ; 6
|
||||
|
||||
|
||||
reset_chunk:
|
||||
lda MB_CHUNK ; reset input pointer ; 3
|
||||
clc ; to the beginning ; 2
|
||||
|
||||
adc #>UNPACK_BUFFER ; in proper chunk (1 of 3) ; 2
|
||||
sta INH ; 3
|
||||
|
||||
|
||||
;============
|
||||
; 18
|
||||
done_interrupt:
|
||||
pla ; restore a ; 4
|
||||
|
||||
rti ; return from interrupt ; 6
|
||||
|
||||
;============
|
||||
; typical
|
||||
; 1358 cycles
|
||||
|
||||
Loading…
Reference in New Issue