oscar64/include/c64/rasterirq.c

368 lines
5.0 KiB
C

#include "rasterirq.h"
#include <c64/vic.h>
#include <c64/cia.h>
#include <c64/asm6502.h>
#include <stdlib.h>
volatile char npos = 1, tpos = 0;
byte rasterIRQRows[NUM_IRQS];
byte rasterIRQIndex[NUM_IRQS];
byte rasterIRQNext[NUM_IRQS];
byte rasterIRQLow[NUM_IRQS];
byte rasterIRQHigh[NUM_IRQS];
byte nextIRQ;
__asm irq0
{
pha
txa
pha
tya
pha
ldx nextIRQ
l1:
lda rasterIRQNext, x
cmp #$ff
beq e1
ldy rasterIRQIndex, x
tax
lda rasterIRQLow, y
sta ji + 1
lda rasterIRQHigh, y
sta ji + 2
ji:
jsr $0000
jx:
inc nextIRQ
ldx nextIRQ
lda rasterIRQNext, x
cmp #$ff
beq e2
tay
sec
sbc #4
cmp $d012
bcc l1
dey
sty $d012
w1:
jmp ex
e2:
ldx npos
stx tpos
bit $d011
bmi e1
sta $d012
asl $d019
jmp ex
e1:
ldx #0
stx nextIRQ
lda rasterIRQNext, x
sec
sbc #1
sta $d012
ex:
asl $d019
pla
tay
pla
tax
pla
rti
}
__asm irq1
{
lda $d019
bpl ex2
ldx nextIRQ
l1:
lda rasterIRQNext, x
cmp #$ff
beq e1
ldy rasterIRQIndex, x
tax
lda rasterIRQLow, y
sta ji + 1
lda rasterIRQHigh, y
sta ji + 2
ji:
jsr $0000
jx:
inc nextIRQ
ldx nextIRQ
lda rasterIRQNext, x
cmp #$ff
beq e2
tay
sec
sbc #4
cmp $d012
bcc l1
dey
sty $d012
w1:
jmp ex
e2:
ldx npos
stx tpos
bit $d011
bmi e1
sta $d012
jmp ex
e1:
ldx #0
stx nextIRQ
lda rasterIRQNext, x
sec
sbc #1
sta $d012
ex:
asl $d019
jmp $ea81
ex2:
LDA $DC0D
cli
jmp $ea31
}
// 0 lda #data0
// 2 ldy #data1
// 4 cpx $d012
// 7 bcc -5
// 9 sta addr0
// 12 sty addr1
// 15 lda #data2
// 17 sta addr2
// 20 lda #data3
// 22 sta addr3
// ...
// rts
void rirq_build(RIRQCode * ic, byte size)
{
ic->size = size;
asm_im(ic->code + 0, ASM_LDY, 0);
asm_im(ic->code + 2, ASM_LDA, 0);
asm_ab(ic->code + 4, ASM_CPX, 0xd012);
asm_rl(ic->code + 7, ASM_BCS, -5);
asm_ab(ic->code + 9, ASM_STY, 0x0000);
if (size == 1)
{
asm_np(ic->code + 12, ASM_RTS);
}
else
{
asm_ab(ic->code + 12, ASM_STA, 0x0000);
byte p = 15;
for(byte i=2; i<size; i++)
{
p += asm_im(ic->code + p, ASM_LDA, 0x00);
p += asm_ab(ic->code + p, ASM_STA, 0x0000);
}
asm_np(ic->code + p, ASM_RTS);
}
}
RIRQCode * rirq_alloc(byte size)
{
RIRQCode * ic = (RIRQCode *)malloc(1 + RIRQ_SIZE + 5 * size);
rirq_build(ic, size);
return ic;
}
#pragma native(rirq_build)
void rirq_set(byte n, byte row, RIRQCode * write)
{
rasterIRQLow[n] = (unsigned)&write->code & 0xff;
rasterIRQHigh[n] = (unsigned)&write->code >> 8;
rasterIRQRows[n] = row;
}
static const byte irqai[16] = {
RIRQ_ADDR_0, RIRQ_ADDR_1, RIRQ_ADDR_2, RIRQ_ADDR_3, RIRQ_ADDR_4, RIRQ_ADDR_5, RIRQ_ADDR_6, RIRQ_ADDR_7,
RIRQ_ADDR_8, RIRQ_ADDR_9, RIRQ_ADDR_10, RIRQ_ADDR_11, RIRQ_ADDR_12, RIRQ_ADDR_13, RIRQ_ADDR_14, RIRQ_ADDR_15
};
static const byte irqdi[16] = {
RIRQ_DATA_0, RIRQ_DATA_1, RIRQ_DATA_2, RIRQ_DATA_3, RIRQ_DATA_4, RIRQ_DATA_5, RIRQ_DATA_6, RIRQ_DATA_7,
RIRQ_DATA_8, RIRQ_DATA_9, RIRQ_DATA_10, RIRQ_DATA_11, RIRQ_DATA_12, RIRQ_DATA_13, RIRQ_DATA_14, RIRQ_DATA_15
};
void rirq_addr(RIRQCode * ic, byte n, void * addr)
{
byte p = irqai[n];
ic->code[p + 0] = (unsigned)addr & 0xff;
ic->code[p + 1] = (unsigned)addr >> 8;
}
void rirq_data(RIRQCode * ic, byte n, byte data)
{
byte p = irqdi[n];
ic->code[p] = data;
}
void rirq_write(RIRQCode * ic, byte n, void * addr, byte data)
{
byte p = irqai[n];
ic->code[p + 0] = (unsigned)addr & 0xff;
ic->code[p + 1] = (unsigned)addr >> 8;
p = irqdi[n];
ic->code[p] = data;
}
void rirq_call(RIRQCode * ic, byte n, void * addr)
{
byte p = irqai[n];
ic->code[p - 1] = 0x20;
ic->code[p + 0] = (unsigned)addr & 0xff;
ic->code[p + 1] = (unsigned)addr >> 8;
}
void rirq_delay(RIRQCode * ic, byte cycles)
{
ic->code[ 1] = cycles;
ic->code[ 9] = 0x88; // dey
ic->code[10] = 0xd0; // bne
ic->code[11] = 0xfd; // -3
}
void rirq_move(byte n, byte row)
{
rasterIRQRows[n] = row;
}
void rirq_clear(byte n)
{
rasterIRQRows[n] = 255;
}
void rirq_init(bool kernalIRQ)
{
for(byte i=0; i<NUM_IRQS; i++)
{
rasterIRQRows[i] = 255;
rasterIRQIndex[i] = i;
}
__asm
{
sei
#if 0
// disable CIA interrupts
lda #$7f
sta $dc0d
sta $dd0d
#endif
}
if (kernalIRQ)
*(void **)0x0314 = irq1;
else
*(void **)0xfffe = irq0;
vic.intr_enable = 1;
vic.ctrl1 &= 0x7f;
vic.raster = 255;
}
void rirq_wait(void)
{
while (tpos != npos) ;
npos++;
}
void rirq_sort(void)
{
for(byte i = 1; i<NUM_IRQS; i++)
{
byte ri = rasterIRQIndex[i];
byte rr = rasterIRQRows[ri];
byte j = i, rj;
while (j > 0 && rr < rasterIRQRows[(rj = rasterIRQIndex[j - 1])])
{
rasterIRQIndex[j] = rj;
j--;
}
rasterIRQIndex[j] = ri;
}
for(byte i=0; i<NUM_IRQS; i++)
rasterIRQNext[i] = rasterIRQRows[rasterIRQIndex[i]];
npos++;
vic.raster = rasterIRQNext[nextIRQ] - 1;
}
void rirq_start(void)
{
__asm
{
lda $d011
and #$7f
sta $d011
lda #100
sta $d012
cli
}
}
void rirq_stop(void)
{
__asm
{
sei
}
}
#pragma native(rirq_sort)
#pragma native(rirq_wait)
#pragma native(rirq_start)
#pragma native(rirq_stop)