ref: a7c01127f9749fe471367c6461cde357403cc3b3
dir: /sys/src/games/snes/cpu.c/
#include <u.h>
#include <libc.h>
#include <thread.h>
#include "../eui.h"
#include "dat.h"
#include "fns.h"
u8int rP, emu, irq, nmi, dma, wai;
u16int rA, rX, rY, rS, rD, pc;
u32int rDB, rPB, curpc, hdma;
static u8int m8, x8;
int cyc;
static u32int lastpc;
#define io() cyc += 6
static void
ioirq(void)
{
if(irq && (rP & FLAGI) == 0)
memread(pc | rPB);
else
io();
}
static u8int
fetch8(void)
{
return memread(pc++ | rPB);
}
static u16int
fetch16(void)
{
u16int r;
r = memread(pc++ | rPB);
r |= memread(pc++ | rPB) << 8;
return r;
}
static u16int
mem16(u32int a)
{
u16int r;
r = memread(a++);
r |= memread(a) << 8;
return r;
}
static u16int
mem816(u32int a, u16int v)
{
if(m8)
return memread(a) | v;
return mem16(a);
}
static u16int
memx816(u32int a)
{
if(x8)
return memread(a);
return mem16(a);
}
static void
memw816(u32int a, u16int v)
{
memwrite(a, v);
if(m8)
return;
memwrite(++a, v >> 8);
}
static void
memwx816(u32int a, u16int v)
{
memwrite(a, v);
if(x8)
return;
memwrite(++a, v >> 8);
}
static void
push8(u8int a)
{
memwrite(rS, a);
if(emu && (rS & 0xFF) == 0)
rS |= 0xFF;
else
rS--;
}
static u8int
pop8(void)
{
if(emu && (rS & 0xFF) == 0xFF)
rS &= ~0xFF;
else
rS++;
return memread(rS);
}
static void
push16(u16int a)
{
push8(a >> 8);
push8(a);
}
static u16int
pop16(void)
{
u16int r;
r = pop8();
r |= pop8() << 8;
return r;
}
static void
push816(u16int v, int m)
{
if(!m)
push8(v >> 8);
push8(v);
}
static u16int
pop816(u16int a, int m)
{
u16int r;
r = pop8();
if(m)
return r | a;
r |= pop8() << 8;
return r;
}
static u16int
nz8(u16int v)
{
rP &= ~(FLAGN | FLAGZ);
if((v & 0xFF) == 0)
rP |= FLAGZ;
rP |= (v & 0x80);
return v;
}
static u16int
nz16(u16int v)
{
rP &= ~(FLAGN | FLAGZ);
if(v == 0)
rP |= FLAGZ;
if((v & 0x8000) != 0)
rP |= FLAGN;
return v;
}
static u16int
nz(u16int v)
{
if(m8)
return nz8(v);
return nz16(v);
}
static u16int
nzx(u16int v)
{
if(x8)
return nz8(v);
return nz16(v);
}
static u16int
imm(int a)
{
if(m8)
return fetch8() | a;
return fetch16();
}
static u16int
immx(int a)
{
if(x8)
return fetch8() | a;
return fetch16();
}
static u32int
abso(int l, int x)
{
u32int p;
p = fetch16();
if(l)
p |= fetch8() << 16;
else
p |= rDB;
switch(x){
case 1: p += rX; break;
case 2: p += rY; break;
}
return p;
}
static u32int
absi(int x)
{
u16int p;
u32int b, r;
p = fetch16();
if(x){
p += rX;
b = rPB;
io();
}else
b = 0;
r = memread(p++ | b);
r |= memread(p | b) << 8;
return r;
}
static u32int
dp(int x)
{
u32int p;
p = fetch8();
switch(x){
case 1: p += rX; io(); break;
case 2: p += rY; io(); break;
}
if((rD & 0xFF) != 0)
io();
else if(emu)
return rD & 0xFF00 | p & 0xFF;
p = (p + rD) & 0xFFFF;
return p;
}
static u32int
dpi(int l, int x, int y)
{
u32int p, r, s;
u32int b;
p = dp(x);
r = memread(p++);
if(emu && (rD & 0xFF) == 0){
if((p & 0xFF) == 0)
p -= 0x100;
}else
p &= 0xFFFF;
r |= memread(p++) << 8;
if(l){
if(emu && (rD & 0xFF) == 0){
if((p & 0xFF) == 0)
p -= 0x100;
}else
p &= 0xFFFF;
b = memread(p) << 16;
}else
b = rDB;
if(y){
s = r + rY;
if(x8 && ((r ^ s) & 0xFF00) != 0)
io();
r = s;
}
r += b;
return r;
}
static u32int
sr(void)
{
u8int d;
d = fetch8();
io();
return (rS + d) & 0xFFFF;
}
static u32int
sry(void)
{
u8int d;
u32int a;
d = fetch8();
io();
a = (mem16((rS + d) & 0xFFFF) | rDB) + rY;
io();
return a;
}
static void
rmw(u32int a, u16int, u16int w)
{
io();
memw816(a, w);
nz(w);
}
static void
branch(int c)
{
signed char t;
u16int npc;
t = fetch8();
if(!c)
return;
npc = pc + t;
io();
if(emu && (npc ^ pc) >> 8)
io();
pc = npc;
}
static void
setrp(u8int v)
{
if(emu)
v |= 0x30;
else if((v & 0x10) != 0){
rX &= 0xff;
rY &= 0xff;
}
rP = v;
}
static void
adc(u16int a)
{
int r;
if(m8){
if((rP & FLAGD) != 0){
r = (rA & 0xf) + (a & 0xf) + (rP & FLAGC);
if(r > 0x09)
r += 0x06;
if(r > 0x1f)
r -= 0x10;
r += (rA & 0xf0) + (a & 0xf0);
}else
r = (rA & 0xff) + a + (rP & FLAGC);
rP &= ~(FLAGC | FLAGN | FLAGV | FLAGZ);
if((~(rA ^ a) & (rA ^ r)) & 0x80)
rP |= FLAGV;
if((rP & FLAGD) != 0 && r > 0x9f)
r += 0x60;
if(r > 0xFF)
rP |= FLAGC;
rP |= r & 0x80;
r &= 0xFF;
if(r == 0)
rP |= FLAGZ;
rA = rA & 0xFF00 | r;
}else{
if((rP & FLAGD) != 0){
r = (rA & 0x000f) + (a & 0x000f) + (rP & FLAGC);
if(r > 0x0009) r += 0x0006;
if(r > 0x001f) r -= 0x0010;
r += (rA & 0x00f0) + (a & 0x00f0);
if(r > 0x009f) r += 0x0060;
if(r > 0x01ff) r -= 0x0100;
r += (rA & 0x0f00) + (a & 0x0f00);
if(r > 0x09ff) r += 0x0600;
if(r > 0x1fff) r -= 0x1000;
r += (rA & 0xf000) + (a & 0xf000);
}else
r = rA + a + (rP & FLAGC);
rP &= ~(FLAGC | FLAGN | FLAGV | FLAGZ);
if((~(rA ^ a) & (rA ^ r)) & 0x8000)
rP |= FLAGV;
if((rP & FLAGD) != 0 && r > 0x9fff)
r += 0x6000;
if(r > 0xFFFF)
rP |= FLAGC;
if((r & 0x8000) != 0)
rP |= FLAGN;
rA = r;
if(rA == 0)
rP |= FLAGZ;
}
}
static void
asl(u32int a)
{
u16int v;
v = mem816(a, 0);
rP &= ~FLAGC;
rP |= v >> (m8 ? 7 : 15);
rmw(a, v, v << 1);
}
static void
bit(u16int a)
{
rP &= ~(FLAGN | FLAGZ | FLAGV);
if((a & rA) == 0)
rP |= FLAGZ;
if(m8)
rP |= a & 0xC0;
else
rP |= (a >> 8) & 0xC0;
}
static void
block(int incr)
{
u32int sb;
rDB = fetch8() << 16;
sb = fetch8() << 16;
memwrite(rDB | rY, memread(sb | rX));
if(incr){
rX++;
rY++;
}else{
rX--;
rY--;
}
if(x8){
rX &= 0xff;
rY &= 0xff;
}
if(rA-- != 0)
pc -= 3;
io();
io();
}
static void
cmp(u16int a, u16int b, int m)
{
if(m){
a &= 0xff;
b &= 0xff;
}
rP &= ~(FLAGN | FLAGZ | FLAGC);
if(a == b)
rP |= FLAGZ;
if(a >= b)
rP |= FLAGC;
if((a - b) & (m ? 0x80 : 0x8000))
rP |= FLAGN;
}
static void
dec(u32int a)
{
u16int v;
v = mem816(a, 0);
rmw(a, v, v-1);
}
static void
inc(u32int a)
{
u16int v;
v = mem816(a, 0);
rmw(a, v, v+1);
}
static void
lsr(u32int a)
{
u16int v;
v = mem816(a, 0);
rP &= ~FLAGC;
rP |= v & 1;
rmw(a, v, v>>1);
}
static void
rol(u32int a)
{
u16int v, w;
v = rP & FLAGC;
w = mem816(a, 0);
rP &= ~FLAGC;
rP |= w >> (m8 ? 7 : 15);
rmw(a, w, w<<1 | v);
}
static void
ror(u32int a)
{
u16int v, w;
v = (rP & FLAGC) << (m8 ? 7 : 15);
w = mem816(a, 0);
rP &= ~FLAGC;
rP |= w & 1;
rmw(a, w, w>>1 | v);
}
static void
sbc(u16int a)
{
int r;
if(m8){
a ^= 0xff;
if((rP & FLAGD) != 0){
r = (rA & 0xf) + (a & 0xf) + (rP & FLAGC);
if(r < 0x10) r -= 0x06;
if(r < 0) r += 0x10;
r += (rA & 0xf0) + (a & 0xf0);
}else
r = (rA & 0xff) + a + (rP & FLAGC);
rP &= ~(FLAGC | FLAGN | FLAGV | FLAGZ);
if((~(rA ^ a) & (rA ^ r)) & 0x80)
rP |= FLAGV;
if(r > 0xff)
rP |= FLAGC;
else if((rP & FLAGD) != 0)
r -= 0x60;
rP |= r & 0x80;
r &= 0xFF;
if(r == 0)
rP |= FLAGZ;
rA = rA & 0xFF00 | r;
}else{
a ^= 0xffff;
if((rP & FLAGD) != 0){
r = (rA & 0x000f) + (a & 0x000f) + (rP & FLAGC);
if(r < 0x0010) r -= 0x0006;
if(r < 0x0000) r += 0x0010;
r += (rA & 0x00f0) + (a & 0x00f0);
if(r < 0x0100) r -= 0x0060;
if(r < 0x0000) r += 0x0100;
r += (rA & 0x0f00) + (a & 0x0f00);
if(r < 0x1000) r -= 0x0600;
if(r < 0x0000) r += 0x1000;
r += (rA & 0xf000) + (a & 0xf000);
}else
r = rA + a + (rP & FLAGC);
rP &= ~(FLAGC | FLAGN | FLAGV | FLAGZ);
if((~(rA ^ a) & (rA ^ r)) & 0x8000)
rP |= FLAGV;
if(r > 0xFFFF)
rP |= FLAGC;
else if((rP & FLAGD) != 0)
r -= 0x6000;
if((r & 0x8000) != 0)
rP |= FLAGN;
rA = r;
if(rA == 0)
rP |= FLAGZ;
}
}
static void
setra(u16int a)
{
if(m8)
rA = rA & 0xff00 | nz8(a & 0xff);
else
rA = nz16(a);
}
static void
setx(u16int a, u16int *b)
{
if(x8)
*b = nz8(a & 0xff);
else
*b = nz16(a);
}
static void
tsb(u32int a, int set)
{
u16int v;
v = mem816(a, 0);
rP &= ~FLAGZ;
if(m8){
if((rA & v & 0xFF) == 0)
rP |= FLAGZ;
}else
if((rA & v) == 0)
rP |= FLAGZ;
io();
if(set)
memw816(a, v | rA);
else
memw816(a, v & ~rA);
}
enum { COP = 0, BRK = 1, NMI = 3, IRQ = 5 };
static void
interrupt(int src)
{
if(src > BRK)
memread(pc | rPB);
if(!emu)
push8(rPB >> 16);
push16(pc);
if(emu && src != BRK)
push8(rP & ~(1<<5));
else
push8(rP);
if(emu && src == BRK)
src = IRQ;
pc = mem16(0xffe4 + src * 2 + emu * 0x10);
rP |= FLAGI;
rP &= ~FLAGD;
rPB = 0;
if(emu)
rDB = 0;
wai = 0;
}
void
cpureset(void)
{
pc = mem16(0xfffc);
rD = 0;
rDB = 0;
rPB = 0;
rS = 0x100;
rP = 0x35;
}
int
cpustep(void)
{
u8int op;
int a;
static int cnt;
cyc = 0;
if((hdma & 0xffff) != 0){
curpc = -1;
return hdmastep();
}
if(dma){
curpc = -1;
return dmastep();
}
if(nmi)
if(--nmi == 0){
interrupt(NMI);
return cyc;
}
if(irq && (rP & FLAGI) == 0){
interrupt(IRQ);
return cyc;
}
curpc = pc|rPB;
if(wai){
io();
if(irq){
wai = 0;
io();
}else
return cyc;
}
m8 = (rP & FLAGM) != 0;
x8 = (rP & FLAGX) != 0;
op = fetch8();
if(op == 0)
print("BRK PC=%.6x from PC=%.6x\n", curpc, lastpc);
lastpc = curpc;
if(trace)
print("%.6x %.2x A=%.4x X=%.4x Y=%.4x P=%.2x %.2x\n", curpc, op, rA, rX, rY, rP, rS);
switch(op){
case 0x00: fetch8(); interrupt(BRK); break;
case 0x01: nz(rA |= mem816(dpi(0, 1, 0), 0)); break;
case 0x02: fetch8(); interrupt(COP); break;
case 0x03: nz(rA |= mem816(sr(), 0)); break;
case 0x04: tsb(dp(0), 1); break;
case 0x05: nz(rA |= mem816(dp(0), 0)); break;
case 0x06: asl(dp(0)); break;
case 0x07: nz(rA |= mem816(dpi(1, 0, 0), 0)); break;
case 0x08: io(); push8(rP); break;
case 0x09: nz(rA |= imm(0)); break;
case 0x0A:
rP &= ~FLAGC;
if(m8){
rP |= (rA >> 7) & 1;
rA = (rA & 0xFF00) | ((rA << 1) & 0xFF);
}else{
rP |= (rA >> 15) & 1;
rA <<= 1;
}
nz(rA);
ioirq();
break;
case 0x0B: io(); push16(rD); break;
case 0x0C: tsb(abso(0, 0), 1); break;
case 0x0D: nz(rA |= mem816(abso(0, 0), 0)); break;
case 0x0E: asl(abso(0, 0)); break;
case 0x0F: nz(rA |= mem816(abso(1, 0), 0)); break;
case 0x10: branch((rP & FLAGN) == 0); break;
case 0x11: nz(rA |= mem816(dpi(0, 0, 1), 0)); break;
case 0x12: nz(rA |= mem816(dpi(0, 0, 0), 0)); break;
case 0x13: nz(rA |= mem816(sry(), 0)); break;
case 0x14: tsb(dp(0), 0); break;
case 0x15: nz(rA |= mem816(dp(1), 0)); break;
case 0x16: asl(dp(1)); break;
case 0x17: nz(rA |= mem816(dpi(1, 0, 1), 0)); break;
case 0x18: rP &= ~FLAGC; ioirq(); break;
case 0x19: nz(rA |= mem816(abso(0, 2), 0)); break;
case 0x1A:
if(m8 && (rA & 0xFF) == 0xFF)
rA &= ~0xFF;
else
rA++;
nz(rA);
ioirq();
break;
case 0x1B: rS = rA; if(emu) rS = rS & 0xff | 0x100; ioirq(); break;
case 0x1C: tsb(abso(0, 0), 0); break;
case 0x1D: nz(rA |= mem816(abso(0, 1), 0)); break;
case 0x1E: asl(abso(0, 1)); break;
case 0x1F: nz(rA |= mem816(abso(1, 1), 0)); break;
case 0x20: a = fetch16(); io(); push16(pc-1); pc = a; break;
case 0x21: nz(rA &= mem816(dpi(0, 1, 0), 0xFF00)); break;
case 0x22: a = fetch16(); push8(rPB>>16); io(); rPB = fetch8()<<16; push16(pc-1); pc = a; break;
case 0x23: nz(rA &= mem816(sr(), 0xFF00)); break;
case 0x24: bit(mem816(dp(0), 0)); break;
case 0x25: nz(rA &= mem816(dp(0), 0xFF00)); break;
case 0x26: rol(dp(0)); break;
case 0x27: nz(rA &= mem816(dpi(1, 0, 0), 0xFF00)); break;
case 0x28: io(); io(); setrp(pop8()); break;
case 0x29: nz(rA &= imm(0xFF00)); break;
case 0x2A:
a = rP & FLAGC;
rP &= ~FLAGC;
if(m8){
rP |= (rA >> 7) & 1;
rA = (rA & 0xFF00) | ((rA << 1) & 0xFF) | a;
}else{
rP |= (rA >> 15) & 1;
rA = (rA << 1) | a;
}
nz(rA);
ioirq();
break;
case 0x2B: io(); io(); nz16(rD = pop16()); break;
case 0x2C: bit(mem816(abso(0, 0), 0)); break;
case 0x2D: nz(rA &= mem816(abso(0, 0), 0xFF00)); break;
case 0x2E: rol(abso(0, 0)); break;
case 0x2F: nz(rA &= mem816(abso(1, 0), 0xFF00)); break;
case 0x30: branch((rP & FLAGN) != 0); break;
case 0x31: nz(rA &= mem816(dpi(0, 0, 1), 0xFF00)); break;
case 0x32: nz(rA &= mem816(dpi(0, 0, 0), 0xFF00)); break;
case 0x33: nz(rA &= mem816(sry(), 0xFF00)); break;
case 0x34: bit(mem816(dp(1), 0)); break;
case 0x35: nz(rA &= mem816(dp(1), 0xFF00)); break;
case 0x36: rol(dp(1)); break;
case 0x37: nz(rA &= mem816(dpi(1, 0, 1), 0xFF00)); break;
case 0x38: rP |= FLAGC; ioirq(); break;
case 0x39: nz(rA &= mem816(abso(0, 2), 0xFF00)); break;
case 0x3A:
if(m8 && (rA & 0xFF) == 0)
rA |= 0xFF;
else
rA--;
nz(rA);
ioirq();
break;
case 0x3B: nz16(rA = rS); ioirq(); break;
case 0x3C: bit(mem816(abso(0, 1), 0)); break;
case 0x3D: nz(rA &= mem816(abso(0, 1), 0xFF00)); break;
case 0x3E: rol(abso(0, 1)); break;
case 0x3F: nz(rA &= mem816(abso(1, 1), 0xFF00)); break;
case 0x40:
io();
io();
setrp(pop8());
pc = pop16();
if(!emu)
rPB = pop8() << 16;
break;
case 0x41: nz(rA ^= mem816(dpi(0, 1, 0), 0)); break;
case 0x42: fetch8(); break;
case 0x43: nz(rA ^= mem816(sr(), 0)); break;
case 0x44: block(0); break;
case 0x45: nz(rA ^= mem816(dp(0), 0)); break;
case 0x46: lsr(dp(0)); break;
case 0x47: nz(rA ^= mem816(dpi(1, 0, 0), 0)); break;
case 0x48: io(); push816(rA, m8); break;
case 0x49: nz(rA ^= imm(0)); break;
case 0x4A:
rP &= ~FLAGC;
rP |= rA & 1;
if(m8)
rA = rA & 0xFF00 | (rA >> 1) & 0x7F;
else
rA >>= 1;
nz(rA);
ioirq();
break;
case 0x4B: io(); push8(rPB >> 16); break;
case 0x4C: pc = fetch16(); break;
case 0x4D: nz(rA ^= mem816(abso(0, 0), 0)); break;
case 0x4E: lsr(abso(0, 0)); break;
case 0x4F: nz(rA ^= mem816(abso(1, 0), 0)); break;
case 0x50: branch((rP & FLAGV) == 0); break;
case 0x51: nz(rA ^= mem816(dpi(0, 0, 1), 0)); break;
case 0x52: nz(rA ^= mem816(dpi(0, 0, 0), 0)); break;
case 0x53: nz(rA ^= mem816(sry(), 0)); break;
case 0x54: block(1); break;
case 0x55: nz(rA ^= mem816(dp(1), 0)); break;
case 0x56: lsr(dp(1)); break;
case 0x57: nz(rA ^= mem816(dpi(1, 0, 1), 0)); break;
case 0x58: rP &= ~FLAGI; ioirq(); break;
case 0x59: nz(rA ^= mem816(abso(0, 2), 0)); break;
case 0x5A: io(); push816(rY, x8); break;
case 0x5B: nz16(rD = rA); ioirq(); break;
case 0x5C: a = fetch16(); rPB = fetch8() << 16; pc = a; break;
case 0x5D: nz(rA ^= mem816(abso(0, 1), 0)); break;
case 0x5E: lsr(abso(0, 1)); break;
case 0x5F: nz(rA ^= mem816(abso(1, 1), 0)); break;
case 0x60: io(); io(); pc = pop16() + 1; io(); break;
case 0x61: adc(mem816(dpi(0, 1, 0), 0)); break;
case 0x62: a = fetch16(); io(); push16(a + pc); break;
case 0x63: adc(mem816(sr(), 0)); break;
case 0x64: memw816(dp(0), 0); break;
case 0x65: adc(mem816(dp(0), 0)); break;
case 0x66: ror(dp(0)); break;
case 0x67: adc(mem816(dpi(1, 0, 0), 0)); break;
case 0x68: nz(rA = pop816(rA & 0xFF00, m8)); break;
case 0x69: adc(imm(0)); break;
case 0x6A:
a = rP & FLAGC;
rP &= ~FLAGC;
rP |= rA & 1;
if(m8)
rA = rA & 0xFF00 | (rA >> 1) & 0x7F | a << 7;
else
rA = rA >> 1 | a << 15;
nz(rA);
ioirq();
break;
case 0x6B: io(); io(); pc = pop16() + 1; rPB = pop8() << 16; break;
case 0x6C: pc = absi(0); break;
case 0x6D: adc(mem816(abso(0, 0), 0)); break;
case 0x6E: ror(abso(0, 0)); break;
case 0x6F: adc(mem816(abso(1, 0), 0)); break;
case 0x70: branch((rP & FLAGV) != 0); break;
case 0x71: adc(mem816(dpi(0, 0, 1), 0)); break;
case 0x72: adc(mem816(dpi(0, 0, 0), 0)); break;
case 0x73: adc(mem816(sry(), 0)); break;
case 0x74: memw816(dp(1), 0); break;
case 0x75: adc(mem816(dp(1), 0)); break;
case 0x76: ror(dp(1)); break;
case 0x77: adc(mem816(dpi(1, 0, 1), 0)); break;
case 0x78: rP |= FLAGI; io(); break;
case 0x79: adc(mem816(abso(0, 2), 0)); break;
case 0x7A: io(); io(); nzx(rY = pop816(0, x8)); break;
case 0x7B: nz16(rA = rD); ioirq(); break;
case 0x7C: pc = absi(1); break;
case 0x7D: adc(mem816(abso(0, 1), 0)); break;
case 0x7E: ror(abso(0, 1)); break;
case 0x7F: adc(mem816(abso(1, 1), 0)); break;
case 0x80: branch(1); break;
case 0x81: memw816(dpi(0, 1, 0), rA); break;
case 0x82: a = fetch16(); io(); pc += a; break;
case 0x83: memw816(sr(), rA); break;
case 0x84: memwx816(dp(0), rY); break;
case 0x85: memw816(dp(0), rA); break;
case 0x86: memwx816(dp(0), rX); break;
case 0x87: memw816(dpi(1, 0, 0), rA); break;
case 0x88:
rY--;
if(x8)
rY &= 0xff;
nzx(rY);
ioirq();
break;
case 0x89:
rP &= ~FLAGZ;
if((imm(0) & rA) == 0)
rP |= FLAGZ;
break;
case 0x8A: setra(rX); ioirq(); break;
case 0x8B: io(); push8(rDB >> 16); break;
case 0x8C: memwx816(abso(0, 0), rY); break;
case 0x8D: memw816(abso(0, 0), rA); break;
case 0x8E: memwx816(abso(0, 0), rX); break;
case 0x8F: memw816(abso(1, 0), rA); break;
case 0x90: branch((rP & FLAGC) == 0); break;
case 0x91: memw816(dpi(0, 0, 1), rA); break;
case 0x92: memw816(dpi(0, 0, 0), rA); break;
case 0x93: memw816(sry(), rA); break;
case 0x94: memwx816(dp(1), rY); break;
case 0x95: memw816(dp(1), rA); break;
case 0x96: memwx816(dp(2), rX); break;
case 0x97: memw816(dpi(1, 0, 1), rA); break;
case 0x98: setra(rY); ioirq(); break;
case 0x99: memw816(abso(0, 2), rA); break;
case 0x9A: rS = rX; if(emu) rS = rS & 0xff | 0x100; ioirq(); break;
case 0x9B: setx(rX, &rY); ioirq(); break;
case 0x9C: memw816(abso(0, 0), 0); break;
case 0x9D: memw816(abso(0, 1), rA); break;
case 0x9E: memw816(abso(0, 1), 0); break;
case 0x9F: memw816(abso(1, 1), rA); break;
case 0xA0: nzx(rY = immx(0)); break;
case 0xA1: nz(rA = mem816(dpi(0, 1, 0), rA & 0xFF00)); break;
case 0xA2: nzx(rX = immx(0)); break;
case 0xA3: nz(rA = mem816(sr(), rA & 0xFF00)); break;
case 0xA4: nzx(rY = memx816(dp(0))); break;
case 0xA5: nz(rA = mem816(dp(0), rA & 0xFF00)); break;
case 0xA6: nzx(rX = memx816(dp(0))); break;
case 0xA7: nz(rA = mem816(dpi(1, 0, 0), rA & 0xFF00)); break;
case 0xA8: setx(rA, &rY); ioirq(); break;
case 0xA9: nz(rA = imm(rA & 0xFF00)); break;
case 0xAA: setx(rA, &rX); ioirq(); break;
case 0xAB: io(); io(); rDB = nz8(pop8()) << 16; break;
case 0xAC: nzx(rY = memx816(abso(0, 0))); break;
case 0xAD: nz(rA = mem816(abso(0, 0), rA & 0xFF00)); break;
case 0xAE: nzx(rX = memx816(abso(0, 0))); break;
case 0xAF: nz(rA = mem816(abso(1, 0), rA & 0xFF00)); break;
case 0xB0: branch((rP & FLAGC) != 0); break;
case 0xB1: nz(rA = mem816(dpi(0, 0, 1), rA & 0xFF00)); break;
case 0xB2: nz(rA = mem816(dpi(0, 0, 0), rA & 0xFF00)); break;
case 0xB3: nz(rA = mem816(sry(), rA & 0xFF00)); break;
case 0xB4: nzx(rY = memx816(dp(1))); break;
case 0xB5: nz(rA = mem816(dp(1), rA & 0xFF00)); break;
case 0xB6: nzx(rX = memx816(dp(2))); break;
case 0xB7: nz(rA = mem816(dpi(1, 0, 1), rA & 0xFF00)); break;
case 0xB8: rP &= ~FLAGV; ioirq(); break;
case 0xB9: nz(rA = mem816(abso(0, 2), rA & 0xFF00)); break;
case 0xBA: setx(rS, &rX); ioirq(); break;
case 0xBB: setx(rY, &rX); ioirq(); break;
case 0xBC: nzx(rY = memx816(abso(0, 1))); break;
case 0xBD: nz(rA = mem816(abso(0, 1), rA & 0xFF00)); break;
case 0xBE: nzx(rX = memx816(abso(0, 2))); break;
case 0xBF: nz(rA = mem816(abso(1, 1), rA & 0xFF00)); break;
case 0xC0: cmp(rY, immx(0), x8); break;
case 0xC1: cmp(rA, mem816(dpi(0, 1, 0), 0), m8); break;
case 0xC2: setrp(rP & ~fetch8()); io(); break;
case 0xC3: cmp(rA, mem816(sr(), 0), m8); break;
case 0xC4: cmp(rY, memx816(dp(0)), x8); break;
case 0xC5: cmp(rA, mem816(dp(0), 0), m8); break;
case 0xC6: dec(dp(0)); break;
case 0xC7: cmp(rA, mem816(dpi(1, 0, 0), 0), m8); break;
case 0xC8:
rY++;
if(x8)
rY &= 0xff;
nzx(rY);
ioirq();
break;
case 0xC9: cmp(rA, imm(0), m8); break;
case 0xCA:
rX--;
if(x8)
rX &= 0xff;
nzx(rX);
ioirq();
break;
case 0xCB: wai = 1; break;
case 0xCC: cmp(rY, memx816(abso(0, 0)), x8); break;
case 0xCD: cmp(rA, mem816(abso(0, 0), 0), m8); break;
case 0xCE: dec(abso(0, 0)); break;
case 0xCF: cmp(rA, mem816(abso(1, 0), 0), m8); break;
case 0xD0: branch((rP & FLAGZ) == 0); break;
case 0xD1: cmp(rA, mem816(dpi(0, 0, 1), 0), m8); break;
case 0xD2: cmp(rA, mem816(dpi(0, 0, 0), 0), m8); break;
case 0xD3: cmp(rA, mem816(sry(), 0), m8); break;
case 0xD4: io(); push16(dpi(0, 0, 0)); break;
case 0xD5: cmp(rA, mem816(dp(1), 0), m8); break;
case 0xD6: dec(dp(1)); break;
case 0xD7: cmp(rA, mem816(dpi(1, 0, 1), 0), m8); break;
case 0xD8: rP &= ~FLAGD; ioirq(); break;
case 0xD9: cmp(rA, mem816(abso(0, 2), 0), m8); break;
case 0xDA: io(); push816(rX, x8); break;
case 0xDB: print("STP\n"); break;
case 0xDC: a = fetch16(); pc = memread(a) | memread((u16int)(a+1))<<8; rPB = memread((u16int)(a+2)) << 16; break;
case 0xDD: cmp(rA, mem816(abso(0, 1), 0), m8); break;
case 0xDE: dec(abso(0, 1)); break;
case 0xDF: cmp(rA, mem816(abso(1, 1), 0), m8); break;
case 0xE0: cmp(rX, immx(0), x8); break;
case 0xE1: sbc(mem816(dpi(0, 1, 0), 0)); break;
case 0xE2: setrp(rP | fetch8()); io(); break;
case 0xE3: sbc(mem816(sr(), 0)); break;
case 0xE4: cmp(rX, memx816(dp(0)), x8); break;
case 0xE5: sbc(mem816(dp(0), 0)); break;
case 0xE6: inc(dp(0)); break;
case 0xE7: sbc(mem816(dpi(1, 0, 0), 0)); break;
case 0xE8:
rX++;
if(x8)
rX &= 0xff;
nzx(rX);
ioirq();
break;
case 0xE9: sbc(imm(0)); break;
case 0xEA: ioirq(); break;
case 0xEB: nz8(rA = (rA >> 8) | (rA << 8)); io(); io(); break;
case 0xEC: cmp(rX, memx816(abso(0, 0)), x8); break;
case 0xED: sbc(mem816(abso(0, 0), 0)); break;
case 0xEE: inc(abso(0, 0)); break;
case 0xEF: sbc(mem816(abso(1, 0), 0)); break;
case 0xF0: branch((rP & FLAGZ) != 0); break;
case 0xF1: sbc(mem816(dpi(0, 0, 1), 0)); break;
case 0xF2: sbc(mem816(dpi(0, 0, 0), 0)); break;
case 0xF3: sbc(mem816(sry(), 0)); break;
case 0xF4: push16(fetch16()); break;
case 0xF5: sbc(mem816(dp(1), 0)); break;
case 0xF6: inc(dp(1)); break;
case 0xF7: sbc(mem816(dpi(1, 0, 1), 0)); break;
case 0xF8: rP |= FLAGD; ioirq(); break;
case 0xF9: sbc(mem816(abso(0, 2), 0)); break;
case 0xFA: nzx(rX = pop816(0, x8)); break;
case 0xFB:
a = emu;
emu = rP & 1;
if(emu){
rX &= 0xff;
rY &= 0xff;
rS = rS & 0xff | 0x100;
rP |= 0x30;
}
rP &= ~1;
rP |= a;
ioirq();
break;
case 0xFC: push16(pc+1); pc = absi(1); break;
case 0xFD: sbc(mem816(abso(0, 1), 0)); break;
case 0xFE: inc(abso(0, 1)); break;
case 0xFF: sbc(mem816(abso(1, 1), 0)); break;
default:
print("undefined %#x (pc %#.6x)\n", op, curpc);
io();
}
return cyc;
}