chiptune_debug: making one last try at this

This commit is contained in:
Vince Weaver 2018-06-11 16:34:23 -04:00
parent b386a4f57a
commit b516b60f51
2 changed files with 290 additions and 1 deletions

View File

@ -5,11 +5,12 @@ PNG2GR = ../gr-utils/png2gr
all: chiptune_debug.dsk
chiptune_debug.dsk: CHIPTUNE_IRQ CHIPTUNE_NOIRQ CHIPTUNE_25HZ ./sdemo.raw
chiptune_debug.dsk: CHIPTUNE_IRQ CHIPTUNE_NOIRQ CHIPTUNE_25HZ CHIPTUNE_BARE ./sdemo.raw
cp chiptune_empty.dsk chiptune_debug.dsk
$(DOS33) -y chiptune_debug.dsk BSAVE -a 0x0C00 CHIPTUNE_IRQ
$(DOS33) -y chiptune_debug.dsk BSAVE -a 0x0C00 CHIPTUNE_NOIRQ
$(DOS33) -y chiptune_debug.dsk BSAVE -a 0x0C00 CHIPTUNE_25HZ
$(DOS33) -y chiptune_debug.dsk BSAVE -a 0x0C00 CHIPTUNE_BARE
CHIPTUNE_IRQ: chiptune_irq.o
@ -40,6 +41,13 @@ chiptune_25Hz.o: chiptune_player.s \
ca65 -D F25HZ=1 -o chiptune_25Hz.o chiptune_player.s -l chiptune_25Hz.lst
CHIPTUNE_BARE: chiptune_bare.o
ld65 -o CHIPTUNE_BARE chiptune_bare.o -C ../linker_scripts/apple2_c00.inc
chiptune_bare.o: chiptune_bare.s
ca65 -o chiptune_bare.o chiptune_bare.s -l chiptune_bare.lst
clean:
rm -f *~ TITLE.GR *.o *.lst \
CHIPTUNE_PLAYER CHIPTUNE_IRQ CHIPTUNE_NOIRQ CHIPTUNE_25HZ

View File

@ -0,0 +1,281 @@
; VMW Chiptune Player
.include "zp.inc"
;=============================
; Setup
;=============================
; init variables
lda #0
sta DONE_PLAYING
sta MB_CHUNK_OFFSET
;============================
; Init the Mockingboard
;============================
jsr mockingboard_init
jsr reset_ay_both
jsr clear_ay_both
;=========================
; Setup Interrupt Handler
;=========================
; Vector address goes to 0x3fe/0x3ff
lda #<interrupt_handler
sta $03fe
lda #>interrupt_handler
sta $03ff
;============================
; Enable 50Hz clock on 6522
;============================
sei ; disable interrupts just in case
lda #$40 ; Continuous interrupts, don't touch PB7
sta $C40B ; ACR register
lda #$7F ; clear all interrupt flags
sta $C40E ; IER register (interrupt enable)
lda #$C0
sta $C40D ; IFR: 1100, enable interrupt on timer one oflow
sta $C40E ; IER: 1100, enable timer one interrupt
lda #$E7
sta $C404 ; write into low-order latch
lda #$4f
sta $C405 ; write into high-order latch,
; load both values into counter
; clear interrupt and start counting
; 4fe7 / 1e6 = .020s, 50Hz
;==================
; load first song
;==================
jsr new_song
;============================
; Enable 6502 interrupts
;============================
cli ; clear interrupt mask
;============================
; Loop forever
;============================
main_loop:
jmp main_loop
;=================
; load a new song
;=================
new_song:
;=========================
; Init Variables
;=========================
lda #$0
sta MB_CHUNK_OFFSET
lda #3
sta CHUNKSIZE
;===========================
; Load in KRW file
;===========================
lda #<UNPACK_BUFFER ; set input pointer
sta INL
lda #>UNPACK_BUFFER
sta INH
; Decompress first chunks
lda #$3
sta CHUNKSIZE
rts
;=========
;routines
;=========
.include "mockingboard_a.s"
;================================
;================================
; mockingboard interrupt handler
;================================
;================================
interrupt_handler:
pha ; save A ; 3
; Should we save X and Y too?
.ifdef NOIRQ
.else
bit $C404 ; clear 6522 interrupt by reading T1C-L ; 4
.endif
mb_play_music:
;======================================
; Write frames to Mockingboard
;======================================
; actually plays frame loaded at end of
; last interrupt, so 20ms behind?
mb_write_frame:
ldx #0 ; set up reg count ; 2
;============
; 2
;==================================
; loop through the 14 registers
; reading the value, then write out
;==================================
; inlined "write_ay_both" to save up to 156 (12*13) cycles
; unrolled
mb_write_loop:
lda REGISTER_DUMP,X ; load register value ; 4
cmp REGISTER_OLD,X ; compare with old values ; 4
beq mb_no_write ; 3/2nt
;=============
; typ 11
; special case R13. If it is 0xff, then don't update
; otherwise might spuriously reset the envelope settings
cpx #13 ; 2
bne mb_not_13 ; 3/2nt
cmp #$ff ; 2
beq mb_skip_13 ; 3/2nt
;============
; typ 5
mb_not_13:
; address
stx MOCK_6522_ORA1 ; put address on PA1 ; 4
stx MOCK_6522_ORA2 ; put address on PA2 ; 4
lda #MOCK_AY_LATCH_ADDR ; latch_address for PB1 ; 2
sta MOCK_6522_ORB1 ; latch_address on PB1 ; 4
sta MOCK_6522_ORB2 ; latch_address on PB2 ; 4
lda #MOCK_AY_INACTIVE ; go inactive ; 2
sta MOCK_6522_ORB1 ; 4
sta MOCK_6522_ORB2 ; 4
; value
lda REGISTER_DUMP,X ; load register value ; 4
sta MOCK_6522_ORA1 ; put value on PA1 ; 4
sta MOCK_6522_ORA2 ; put value on PA2 ; 4
lda #MOCK_AY_WRITE ; ; 2
sta MOCK_6522_ORB1 ; write on PB1 ; 4
sta MOCK_6522_ORB2 ; write on PB2 ; 4
lda #MOCK_AY_INACTIVE ; go inactive ; 2
sta MOCK_6522_ORB1 ; 4
sta MOCK_6522_ORB2 ; 4
;===========
; 62
mb_no_write:
inx ; point to next register ; 2
cpx #14 ; if 14 we're done ; 2
bmi mb_write_loop ; otherwise, loop ; 3/2nt
;============
; 7
mb_skip_13:
;=====================================
; Copy registers to old
;=====================================
ldx #13 ; 2
mb_reg_copy:
lda REGISTER_DUMP,X ; load register value ; 4
sta REGISTER_OLD,X ; compare with old values ; 4
dex ; 2
bpl mb_reg_copy ; 2nt/3
;=============
; 171
;===================================
; Load all 14 registers in advance
;===================================
; note, assuming not cross page boundary, not any slower
; then loading from zero page?
mb_load_values:
ldx #0 ; set up reg count ; 2
ldy MB_CHUNK_OFFSET ; get chunk offset ; 3
;=============
; 5
mb_load_loop:
lda (INL),y ; load register value ; 5
sta REGISTER_DUMP,X ; 4
;============
; 9
;====================
; point to next page
;====================
clc ; point to next interleaved ; 2
lda INH ; page by adding CHUNKSIZE (3/1); 3
adc CHUNKSIZE ; 3
sta INH ; 3
inx ; point to next register ; 2
cpx #14 ; if 14 we're done ; 2
bmi mb_load_loop ; otherwise, loop ; 3/2nt
;============
; 18
;==============================================
; incremement offset. If 0 move to next chunk
;==============================================
increment_offset:
inc MB_CHUNK_OFFSET ; increment offset ; 5
lda #0 ; 2
clc ; 2
adc #>UNPACK_BUFFER ; in proper chunk 1 or 2 ; 2
sta INH ; update r0 pointer ; 3
;=================================
; Finally done with this interrupt
;=================================
done_interrupt:
pla ; restore a ; 4
.ifdef NOIRQ
rts
.else
rti ; return from interrupt ; 6
.endif
REGISTER_OLD:
.byte 0,0,0,0,0,0,0,0,0,0,0,0,0,0
.align 256
UNPACK_BUFFER:
.incbin "sdemo.raw"