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sms vdp, separate SAT parsing

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This commit is contained in:
kub 2021-11-06 21:00:55 +01:00
parent f55ce7bf47
commit 1ce2b0923c
3 changed files with 111 additions and 49 deletions
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32
pico/sms.c
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@ -20,6 +20,7 @@
extern void YM2413_regWrite(unsigned reg);
extern void YM2413_dataWrite(unsigned data);
extern unsigned sprites_status; // TODO put in some hdr file!
static unsigned char vdp_data_read(void)
{
@ -583,7 +584,7 @@ void PicoMemSetupMS(void)
z80_map_set(z80_write_map, 0x0000, 0xbfff, xwrite, 1);
z80_map_set(z80_write_map, 0xc000, 0xdfff, PicoMem.zram, 0);
z80_map_set(z80_write_map, 0xe000, 0xffff, xwrite, 1);
// Nemesis mapper maps last 8KB rom bank #15 to adress 0
if (Pico.ms.mapper == PMS_MAP_NEMESIS && Pico.romsize > 0x1e000)
z80_map_set(z80_read_map, 0x0000, 0x1fff, Pico.rom + 0x1e000, 0);
@ -682,9 +683,15 @@ void PicoFrameMS(void)
PicoFrameStartSMS();
hint = pv->reg[0x0a];
// SMS: xscroll:f3 sprovr,vint, vcount:fc, hint:fd
// GG: xscroll:f5 sprovr,vint:fd vcount:fe, hint:ff
for (y = 0; y < lines; y++)
{
pv->v_counter = Pico.m.scanline = y;
Pico.t.z80c_line_start = Pico.t.z80c_aim;
// advance the line counter. It is set back at some point in the VBLANK so
// that the line count in the active area (-32..lines+1) is contiguous.
pv->v_counter = Pico.m.scanline = (u8)y;
switch (is_pal ? -lines_vis : lines_vis) {
case 192: if (y > 218) pv->v_counter = y - (lines-256); break;
case 224: if (y > 234) pv->v_counter = y - (lines-256); break;
@ -693,14 +700,24 @@ void PicoFrameMS(void)
case -240: if (y > 266) pv->v_counter = y - (lines-256); break;
}
// Parse sprites for the next line
if (y < lines_vis)
PicoParseSATSMS(y-1);
else if (y > lines-32)
PicoParseSATSMS(y-1-lines);
// render next line
if (y < lines_vis && !skip)
PicoLineSMS(y);
Pico.t.z80c_line_start = Pico.t.z80c_aim;
// take over status bits from previously rendered line TODO: cycle exact?
pv->status |= sprites_status;
sprites_status = 0;
// Interrupt handling. Simulate interrupt flagged and immediately reset in
// same insn by flagging the irq, execute for 1 insn, then checking if the
// irq is still pending. (GG Chicago, SMS Back to the Future III)
pv->pending_ints &= ~2; // lost if not caught in the same line
if (y <= lines_vis)
{
if (--hint < 0)
@ -713,11 +730,9 @@ void PicoFrameMS(void)
elprintf(EL_INTS, "hint");
z80_int_assert(1);
}
pv->pending_ints &= ~2; // lost if not caught immediately
}
}
else if (y == lines_vis + 1) {
pv->pending_ints &= ~2;
pv->pending_ints |= 1;
z80_exec(Pico.t.z80c_cnt + 1);
@ -736,13 +751,18 @@ void PicoFrameMS(void)
void PicoFrameDrawOnlyMS(void)
{
struct PicoVideo *pv = &Pico.video;
int lines_vis = 192;
int y;
if ((pv->reg[0] & 6) == 6 && (pv->reg[1] & 0x18))
lines_vis = (pv->reg[1] & 0x08) ? 240 : 224;
PicoFrameStartSMS();
for (y = 0; y < lines_vis; y++)
for (y = 0; y < lines_vis; y++) {
PicoParseSATSMS(y-1);
PicoLineSMS(y);
}
}
// vim:ts=2:sw=2:expandtab