ref: 99db038e2825266e84ddb381718f3d047dc6d733
dir: /sys/src/games/md/z80.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "dat.h" #include "fns.h" u8int s[16], ipage, intm, z80irq; u16int ix[2]; u16int spc, scurpc, sp; int halt; enum { FLAGC = 0x01, FLAGN = 0x02, FLAGV = 0x04, FLAGH = 0x10, FLAGZ = 0x40, FLAGS = 0x80 }; enum { rB, rC, rD, rE, rH, rL, rHL, rA, rF = rHL }; #define BC() (s[rB] << 8 | s[rC]) #define DE() (s[rD] << 8 | s[rE]) #define HL() (s[rH] << 8 | s[rL]) static u8int fetch8(void) { return z80read(spc++); } static u16int fetch16(void) { u16int u; u = z80read(spc++); return u | z80read(spc++) << 8; } static void push8(u8int u) { z80write(--sp, u); } static void push16(u16int u) { z80write(--sp, u >> 8); z80write(--sp, u); } static u8int pop8(void) { return z80read(sp++); } static u16int pop16(void) { u16int v; v = z80read(sp++); return v | z80read(sp++) << 8; } static u16int read16(u16int n) { return z80read(n) | z80read(n+1) << 8; } static void write16(u16int n, u16int v) { z80write(n++, v); z80write(n, v >> 8); } static int parity(u8int v) { return (((v * 0x0101010101010101ULL) & 0x8040201008040201ULL) % 0x1FF) & 1; } static int move(u8int dst, u8int src) { if(dst == rHL){ if(src == rHL){ halt = 1; return 4; } z80write(HL(), s[src]); return 7; } if(src == rHL){ s[dst] = z80read(HL()); return 7; } s[dst] = s[src]; return 4; } static int alu(u8int op, u8int n) { u8int v4; u8int u; u16int v; int t; switch(n){ case 8: u = fetch8(); t = 3; break; case 10: u = ix[0]; t = 4; break; case 11: u = ix[1]; t = 4; break; case 12: u = ix[0] >> 8; t = 4; break; case 13: u = ix[1] >> 8; t = 4; break; case 14: u = z80read(ix[0] + fetch8()); t = 15; break; case 15: u = z80read(ix[1] + fetch8()); t = 15; break; case rHL: u = z80read(HL()); t = 3; break; default: u = s[n]; t = 0; } v4 = 0; switch(op){ default: v4 = (s[rA] & 0x0f) + (u & 0x0f); v = s[rA] + u; break; case 1: v4 = (s[rA] & 0x0f) + (u & 0x0f) + (s[rF] & 1); v = s[rA] + u + (s[rF] & 1); break; case 2: case 7: v4 = (s[rA] & 0x0f) + (~u & 0x0f) + 1; v = s[rA] + (u ^ 0xff) + 1; break; case 3: v4 = (s[rA] & 0x0f) + (~u & 0x0f) + (~s[rF] & 1); v = s[rA] + (u ^ 0xff) + (~s[rF] & 1); break; case 4: v = s[rA] & u; break; case 5: v = s[rA] ^ u; break; case 6: v = s[rA] | u; break; } s[rF] = 0; if((u8int)v == 0) s[rF] |= FLAGZ; if((v & 0x80) != 0) s[rF] |= FLAGS; if(op < 2){ if((v & 0x100) != 0) s[rF] |= FLAGC; if((v4 & 0x10) != 0) s[rF] |= FLAGH; if((~(s[rA] ^ u) & (s[rA] ^ v) & 0x80) != 0) s[rF] |= FLAGV; }else if(op < 4 || op == 7){ s[rF] |= FLAGN; if((v & 0x100) == 0) s[rF] |= FLAGC; if((v4 & 0x10) == 0) s[rF] |= FLAGH; if(((s[rA] ^ u) & (s[rA] ^ v) & 0x80) != 0) s[rF] |= FLAGV; }else{ if(!parity(v)) s[rF] |= FLAGV; if(op == 4) s[rF] |= FLAGH; } if(op != 7) s[rA] = v; return 4+t; } static int branch(int cc, int t) { u16int v; v = (s8int)fetch8(); if(!cc) return t + 7; spc += v; return t + 12; } static u8int inc(u8int v) { s[rF] &= FLAGC; ++v; if(v == 0) s[rF] |= FLAGZ; if((v & 0x80) != 0) s[rF] |= FLAGS; if(v == 0x80) s[rF] |= FLAGV; if((v & 0xf) == 0) s[rF] |= FLAGH; return v; } static u8int dec(u8int v) { --v; s[rF] = s[rF] & FLAGC | FLAGN; if(v == 0) s[rF] |= FLAGZ; if((v & 0x80) != 0) s[rF] |= FLAGS; if(v == 0x7f) s[rF] |= FLAGV; if((v & 0xf) == 0xf) s[rF] |= FLAGH; return v; } static int addhl(u16int u) { u32int v; s[rF] &= ~(FLAGN|FLAGC|FLAGH); v = HL() + u; if((v & 0x10000) != 0) s[rF] |= FLAGC; if((HL() & 0xfff) + (u & 0xfff) >= 0x1000) s[rF] |= FLAGH; s[rL] = v; s[rH] = v >> 8; return 11; } static void adchl(u16int u) { u32int v, v4; v = HL() + u + (s[rF] & FLAGC); v4 = (HL() & 0xfff) + (u & 0xfff) + (s[rF] & FLAGC); s[rF] = 0; if((v & 0x10000) != 0) s[rF] |= FLAGC; if((v4 & 0x1000) != 0) s[rF] |= FLAGH; if((u16int)v == 0) s[rF] |= FLAGZ; if((v & 0x8000) != 0) s[rF] |= FLAGS; if((~(HL() ^ u) & (HL() ^ v) & 0x8000) != 0) s[rF] |= FLAGV; s[rL] = v; s[rH] = v >> 8; } static void sbchl(u16int u) { u32int v, v4; v = HL() + (u16int)~u + (~s[rF] & FLAGC); v4 = (HL() & 0xfff) + (~u & 0xfff) + (~s[rF] & FLAGC); s[rF] = FLAGN; if((v & 0x10000) == 0) s[rF] |= FLAGC; if((v4 & 0x1000) == 0) s[rF] |= FLAGH; if((u16int)v == 0) s[rF] |= FLAGZ; if((v & 0x8000) != 0) s[rF] |= FLAGS; if(((HL() ^ u) & (HL() ^ v) & 0x8000) != 0) s[rF] |= FLAGV; s[rL] = v; s[rH] = v >> 8; } static int addindex(int n, u16int u) { u32int v; s[rF] &= ~(FLAGN|FLAGC|FLAGH); v = ix[n] + u; if((v & 0x10000) != 0) s[rF] |= FLAGC; if((ix[n] & 0xfff) + (u & 0xfff) >= 0x1000) s[rF] |= FLAGH; ix[n] = v; return 15; } static int jump(int cc) { u16int v; v = fetch16(); if(cc) spc = v; return 10; } static int call(u16int a, int cc) { if(!cc) return 10; push16(spc); spc = a; return 17; } static void swap(u8int a) { u8int v; v = s[a]; s[a] = s[a + 8]; s[a + 8] = v; } static int bits(int i) { u8int op, v, n, m, c; u16int a; int t; SET(a, v, t); if(i >= 0){ a = ix[i] + fetch8(); v = z80read(a); t = 23; } op = fetch8(); n = op & 7; m = op >> 3 & 7; if(i < 0){ a = HL(); if(n == 6){ v = z80read(a); t = 15; }else{ v = s[n]; t = 8; } } switch(op >> 6){ case 0: c = s[rF] & FLAGC; switch(m){ default: s[rF] = v >> 7; v = v << 1 | v >> 7; break; case 1: s[rF] = v & 1; v = v >> 1 | v << 7; break; case 2: s[rF] = v >> 7; v = v << 1 | c; break; case 3: s[rF] = v & 1; v = v >> 1 | c << 7; break; case 4: s[rF] = v >> 7; v = v << 1; break; case 5: s[rF] = v & 1; v = v & 0x80 | v >> 1; break; case 6: s[rF] = v >> 7; v = v << 1 | 1; break; case 7: s[rF] = v & 1; v >>= 1; break; } if(v == 0) s[rF] |= FLAGZ; if((v & 0x80) != 0) s[rF] |= FLAGS; if(!parity(v)) s[rF] |= FLAGV; break; case 1: s[rF] = s[rF] & ~(FLAGN|FLAGZ) | FLAGH; if((v & 1<<m) == 0) s[rF] |= FLAGZ; return t; case 2: v &= ~(1<<m); break; case 3: v |= (1<<m); } if(n == 6) z80write(a, v); else s[n] = v; return t; } static int ed(void) { u8int op, v, u, l; u16int a; op = fetch8(); switch(op){ case 0xa0: case 0xa1: case 0xa8: case 0xa9: case 0xb0: case 0xb1: case 0xb8: case 0xb9: switch(op & 3){ default: z80write(DE(), z80read(HL())); s[rF] &= ~(FLAGN|FLAGH); l = 1; break; case 1: u = z80read(HL()); v = s[rA] - u; s[rF] = s[rF] & ~(FLAGS|FLAGZ|FLAGH) | FLAGN; l = v != 0; if((v & 0x80) != 0) s[rF] |= FLAGS; if(v == 0) s[rF] |= FLAGZ; if((s[rA] & 0xf) < (u & 0xf)) s[rF] |= FLAGH; break; } if((op & 8) != 0){ if((op & 3) == 0 && s[rE]-- == 0) s[rD]--; if(s[rL]-- == 0) s[rH]--; }else{ if((op & 3) == 0 && ++s[rE] == 0) s[rD]++; if(++s[rL] == 0) s[rH]++; } if(s[rC]-- == 0) s[rB]--; if((s[rC] | s[rB]) != 0){ s[rF] |= FLAGV; if((op & 0x10) != 0 && l){ spc -= 2; return 21; } }else s[rF] &= ~FLAGV; return 16; case 0x42: sbchl(BC()); return 15; case 0x52: sbchl(DE()); return 15; case 0x62: sbchl(HL()); return 15; case 0x72: sbchl(sp); return 15; case 0x43: write16(fetch16(), BC()); return 20; case 0x53: write16(fetch16(), DE()); return 20; case 0x63: write16(fetch16(), HL()); return 20; case 0x73: write16(fetch16(), sp); return 20; case 0x44: s[rA] = -s[rA]; s[rF] = FLAGN; if(s[rA] == 0) s[rF] |= FLAGZ; else s[rF] |= FLAGC; if((s[rA] & 0x80) != 0) s[rF] |= FLAGS; if(s[rA] == 0x80) s[rF] |= FLAGV; if((s[rA] & 0xf) != 0) s[rF] |= FLAGH; return 8; case 0x46: intm &= 0xc0; return 8; case 0x56: intm = intm & 0xc0 | 1; return 8; case 0x47: ipage = s[rA]; return 9; case 0x57: s[rA] = ipage; return 9; case 0x67: v = z80read(HL()); z80write(HL(), v >> 4 | s[rA] << 4); s[rA] = s[rA] & 0xf0 | v & 0x0f; if(0){ case 0x6f: v = z80read(HL()); z80write(HL(), v << 4 | s[rA] & 0xf); s[rA] = s[rA] & 0xf0 | v >> 4; } s[rF] &= FLAGC; if(s[rA] == 0) s[rF] |= FLAGZ; if((s[rA] & 0x80) != 0) s[rF] |= FLAGS; if(!parity(s[rA])) s[rF] |= FLAGV; return 18; case 0x4a: adchl(BC()); return 15; case 0x5a: adchl(DE()); return 15; case 0x6a: adchl(HL()); return 15; case 0x7a: adchl(sp); return 15; case 0x4b: a = fetch16(); s[rC] = z80read(a++); s[rB] = z80read(a); return 20; case 0x5b: a = fetch16(); s[rE] = z80read(a++); s[rD] = z80read(a); return 20; case 0x6b: a = fetch16(); s[rL] = z80read(a++); s[rH] = z80read(a); return 20; case 0x7b: sp = read16(fetch16()); return 20; case 0x4d: spc = pop16(); return 14; case 0x5e: intm = intm & 0xc0 | 2; return 8; case 0x4f: return 9; } sysfatal("undefined z80 opcode ed%.2x at pc=%#.4x", op, scurpc); return 0; } static int index(int n) { u8int op; u16int v; op = fetch8(); switch(op){ case 0x40: case 0x41: case 0x42: case 0x43: case 0x47: case 0x48: case 0x49: case 0x4a: case 0x4b: case 0x4f: case 0x50: case 0x51: case 0x52: case 0x53: case 0x57: case 0x58: case 0x59: case 0x5a: case 0x5b: case 0x5f: case 0x78: case 0x79: case 0x7a: case 0x7b: case 0x7f: s[op >> 3 & 7] = s[op & 7]; return 8; case 0x60: case 0x61: case 0x62: case 0x63: case 0x67: ix[n] = ix[n] & 0xff | s[op & 7] << 8; return 8; case 0x68: case 0x69: case 0x6a: case 0x6b: case 0x6f: ix[n] = ix[n] & 0xff00 | s[op & 7]; return 8; case 0x65: ix[n] = ix[n] << 8 | ix[n] & 0xff; return 8; case 0x6c: ix[n] = ix[n] >> 8 | ix[n] & 0xff00; return 8; case 0x64: case 0x6d: return 8; case 0x70: case 0x71: case 0x72: case 0x73: case 0x74: case 0x75: case 0x77: z80write(ix[n] + fetch8(), s[op & 7]); return 19; case 0x44: case 0x4c: case 0x54: case 0x5c: case 0x7c: s[op >> 3 & 7] = ix[n] >> 8; return 8; case 0x45: case 0x4d: case 0x55: case 0x5d: case 0x7d: s[op >> 3 & 7] = ix[n]; return 8; case 0x46: case 0x4e: case 0x56: case 0x5e: case 0x66: case 0x6e: case 0x7e: s[op >> 3 & 7] = z80read(ix[n] + fetch8()); return 19; case 0x84: case 0x8c: case 0x94: case 0x9c: case 0xa4: case 0xac: case 0xb4: case 0xbc: return alu(op >> 3 & 7, 12 + n); case 0x85: case 0x8d: case 0x95: case 0x9d: case 0xa5: case 0xad: case 0xb5: case 0xbd: return alu(op >> 3 & 7, 10 + n); case 0x86: case 0x8e: case 0x96: case 0x9e: case 0xa6: case 0xae: case 0xb6: case 0xbe: return alu(op >> 3 & 7, 14 + n); case 0x21: ix[n] = fetch16(); return 14; case 0xe1: ix[n] = pop16(); return 14; case 0x22: write16(fetch16(), ix[n]); return 20; case 0x23: ix[n]++; return 10; case 0xe3: v = ix[n]; ix[n] = read16(sp); write16(sp, v); return 23; case 0x24: inc(ix[n] >> 8); ix[n] += 0x100; return 8; case 0x34: v = ix[n] + fetch8(); z80write(v, inc(z80read(v))); return 23; case 0x25: dec(ix[n] >> 8); ix[n] -= 0x100; return 8; case 0x35: v = ix[n] + fetch8(); z80write(v, dec(z80read(v))); return 23; case 0xe5: push16(ix[n]); return 15; case 0x26: ix[n] = ix[n] & 0xff | fetch8() << 8; return 11; case 0x36: v = ix[n] + fetch8(); z80write(v, fetch8()); return 19; case 0x09: return addindex(n, BC()); case 0x19: return addindex(n, DE()); case 0x29: return addindex(n, ix[n]); case 0x39: return addindex(n, sp); case 0xe9: spc = ix[n]; return 8; case 0xf9: sp = ix[n]; return 10; case 0x2a: ix[n] = read16(fetch16()); return 20; case 0x2b: ix[n]--; return 10; case 0xcb: return bits(n); case 0x2c: inc(ix[n]++); return 8; case 0x2d: dec(ix[n]--); return 8; case 0x2e: ix[n] = ix[n] & 0xff00 | fetch8(); return 11; } sysfatal("undefined z80 opcode %.2x%.2x at pc=%#.4x", n ? 0xfd : 0xdd, op, scurpc); return 0; } int z80step(void) { u8int op; u16int v, w; if((z80bus & RESET) != 0){ scurpc = spc = 0; intm = 0; ipage = 0; return 1; } if((z80bus & BUSACK) != 0){ if((z80bus & BUSREQ) == 0) z80bus &= ~BUSACK; return 1; } if((z80bus & BUSREQ) != 0){ z80bus |= BUSACK; return 1; } if(z80irq != 0 && (intm & 0x80) != 0){ push16(spc); intm &= 0x3f; switch(intm & 3){ case 1: spc = 0x38; return 2; default: sysfatal("z80 interrupt in mode %d", intm & 3); } } scurpc = spc; if(0) print("%x AF %.2x%.2x BC %.2x%.2x DE %.2x%.2x HL %.2x%.2x IX %.4x IY %.4x\n", scurpc, s[rA], s[rF], s[rB], s[rC], s[rD], s[rE], s[rH], s[rL], ix[0], ix[1]); op = fetch8(); switch(op >> 6){ case 1: return move(op >> 3 & 7, op & 7); case 2: return alu(op >> 3 & 7, op & 7); } switch(op){ case 0x00: return 4; case 0x10: return branch(--s[rB] != 0, 1); case 0x20: return branch((s[rF] & FLAGZ) == 0, 0); case 0x30: return branch((s[rF] & FLAGC) == 0, 0); case 0x01: s[rC] = fetch8(); s[rB] = fetch8(); return 10; case 0x11: s[rE] = fetch8(); s[rD] = fetch8(); return 10; case 0x21: s[rL] = fetch8(); s[rH] = fetch8(); return 10; case 0x31: sp = fetch16(); return 10; case 0x02: z80write(BC(), s[rA]); return 7; case 0x12: z80write(DE(), s[rA]); return 7; case 0x22: v = fetch16(); z80write(v++, s[rL]); z80write(v, s[rH]); return 16; case 0x32: z80write(fetch16(), s[rA]); return 13; case 0x03: if(++s[rC] == 0) s[rB]++; return 6; case 0x13: if(++s[rE] == 0) s[rD]++; return 6; case 0x23: if(++s[rL] == 0) s[rH]++; return 6; case 0x33: sp++; return 6; case 0x04: inc(s[rB]++); return 4; case 0x14: inc(s[rD]++); return 4; case 0x24: inc(s[rH]++); return 4; case 0x34: z80write(HL(), inc(z80read(HL()))); return 11; case 0x05: dec(s[rB]--); return 4; case 0x15: dec(s[rD]--); return 4; case 0x25: dec(s[rH]--); return 4; case 0x35: z80write(HL(), dec(z80read(HL()))); return 11; case 0x06: s[rB] = fetch8(); return 7; case 0x16: s[rD] = fetch8(); return 7; case 0x26: s[rH] = fetch8(); return 7; case 0x36: z80write(HL(), fetch8()); return 10; case 0x07: s[rF] = s[rF] & ~(FLAGC|FLAGN|FLAGH) | s[rA] >> 7; s[rA] = s[rA] << 1 | s[rA] >> 7; return 4; case 0x17: v = s[rF] & FLAGC; s[rF] = s[rF] & ~(FLAGC|FLAGN|FLAGH) | s[rA] >> 7; s[rA] = s[rA] << 1 | v; return 4; case 0x27: if(s[rA] > 0x99 || (s[rF] & FLAGC) != 0){ s[rF] |= FLAGC; v = 0x60; }else{ s[rF] &= ~FLAGC; v = 0; } if((s[rA] & 0xf) > 9 || (s[rF] & FLAGH) != 0) v |= 6; w = s[rA]; if((s[rF] & FLAGN) != 0) s[rA] -= v; else s[rA] += v; s[rF] &= ~(FLAGV|FLAGS|FLAGZ|FLAGH); if(((s[rA] ^ w) & 0x10) != 0) s[rF] |= FLAGH; if(!parity(s[rA])) s[rF] |= FLAGV; if(s[rA] == 0) s[rF] |= FLAGZ; if((s[rA] & 0x80) != 0) s[rF] |= FLAGS; return 4; case 0x37: s[rF] = s[rF] & ~(FLAGN | FLAGH) | FLAGC; return 4; case 0x08: swap(rA); swap(rF); return 4; case 0x18: return branch(1, 0); case 0x28: return branch((s[rF] & FLAGZ) != 0, 0); case 0x38: return branch((s[rF] & FLAGC) != 0, 0); case 0x09: return addhl(BC()); case 0x19: return addhl(DE()); case 0x29: return addhl(HL()); case 0x39: return addhl(sp); case 0x0a: s[rA] = z80read(BC()); return 7; case 0x1a: s[rA] = z80read(DE()); return 7; case 0x2a: v = fetch16(); s[rL] = z80read(v++); s[rH] = z80read(v); return 16; case 0x3a: s[rA] = z80read(fetch16()); return 13; case 0x0b: if(s[rC]-- == 0) s[rB]--; return 6; case 0x1b: if(s[rE]-- == 0) s[rD]--; return 6; case 0x2b: if(s[rL]-- == 0) s[rH]--; return 6; case 0x3b: sp--; return 6; case 0x0c: inc(s[rC]++); return 4; case 0x1c: inc(s[rE]++); return 4; case 0x2c: inc(s[rL]++); return 4; case 0x3c: inc(s[rA]++); return 4; case 0x0d: dec(s[rC]--); return 4; case 0x1d: dec(s[rE]--); return 4; case 0x2d: dec(s[rL]--); return 4; case 0x3d: dec(s[rA]--); return 4; case 0x0e: s[rC] = fetch8(); return 7; case 0x1e: s[rE] = fetch8(); return 7; case 0x2e: s[rL] = fetch8(); return 7; case 0x3e: s[rA] = fetch8(); return 7; case 0x0f: s[rF] = s[rF] & ~(FLAGC|FLAGN|FLAGH) | s[rA] & 1; s[rA] = s[rA] >> 1 | s[rA] << 7; return 4; case 0x1f: v = s[rF] << 7; s[rF] = s[rF] & ~(FLAGC|FLAGN|FLAGH) | s[rA] & 1; s[rA] = s[rA] >> 1 | v; return 4; case 0x2f: s[rF] |= FLAGN|FLAGH; s[rA] ^= 0xff; return 4; case 0x3f: s[rF] = s[rF] & ~(FLAGN|FLAGH) ^ FLAGC | s[rF] << 4 & FLAGH; return 4; case 0xc0: if((s[rF] & FLAGZ) == 0) {spc = pop16(); return 11;} return 5; case 0xd0: if((s[rF] & FLAGC) == 0) {spc = pop16(); return 11;} return 5; case 0xe0: if((s[rF] & FLAGV) == 0) {spc = pop16(); return 11;} return 5; case 0xf0: if((s[rF] & FLAGS) == 0) {spc = pop16(); return 11;} return 5; case 0xc1: s[rC] = pop8(); s[rB] = pop8(); return 10; case 0xd1: s[rE] = pop8(); s[rD] = pop8(); return 10; case 0xe1: s[rL] = pop8(); s[rH] = pop8(); return 10; case 0xf1: s[rF] = pop8(); s[rA] = pop8(); return 10; case 0xc2: return jump((s[rF] & FLAGZ) == 0); case 0xd2: return jump((s[rF] & FLAGC) == 0); case 0xe2: return jump((s[rF] & FLAGV) == 0); case 0xf2: return jump((s[rF] & FLAGS) == 0); case 0xc3: return jump(1); case 0xd3: z80out(fetch8(), s[rA]); return 11; case 0xe3: v = HL(); s[rL] = z80read(sp); s[rH] = z80read(sp + 1); write16(sp, v); return 19; case 0xf3: intm &= 0x3f; return 4; case 0xc4: return call(fetch16(), (s[rF] & FLAGZ) == 0); case 0xd4: return call(fetch16(), (s[rF] & FLAGC) == 0); case 0xe4: return call(fetch16(), (s[rF] & FLAGV) == 0); case 0xf4: return call(fetch16(), (s[rF] & FLAGS) == 0); case 0xc5: push8(s[rB]); push8(s[rC]); return 11; case 0xd5: push8(s[rD]); push8(s[rE]); return 11; case 0xe5: push8(s[rH]); push8(s[rL]); return 11; case 0xf5: push8(s[rA]); push8(s[rF]); return 11; case 0xc6: return alu(0, 8); case 0xd6: return alu(2, 8); case 0xe6: return alu(4, 8); case 0xf6: return alu(6, 8); case 0xc7: return call(0x00, 1); case 0xd7: return call(0x10, 1); case 0xe7: return call(0x20, 1); case 0xf7: return call(0x30, 1); case 0xc8: if((s[rF] & FLAGZ) != 0) {spc = pop16(); return 11;} return 5; case 0xd8: if((s[rF] & FLAGC) != 0) {spc = pop16(); return 11;} return 5; case 0xe8: if((s[rF] & FLAGV) != 0) {spc = pop16(); return 11;} return 5; case 0xf8: if((s[rF] & FLAGS) != 0) {spc = pop16(); return 11;} return 5; case 0xc9: spc = pop16(); return 10; case 0xd9: swap(rB); swap(rC); swap(rD); swap(rE); swap(rH); swap(rL); return 4; case 0xe9: spc = HL(); return 4; case 0xf9: sp = HL(); return 6; case 0xca: return jump((s[rF] & FLAGZ) != 0); case 0xda: return jump((s[rF] & FLAGC) != 0); case 0xea: return jump((s[rF] & FLAGV) != 0); case 0xfa: return jump((s[rF] & FLAGS) != 0); case 0xcb: return bits(-1); case 0xdb: s[rA] = z80in(fetch8()); return 11; case 0xeb: v = DE(); s[rD] = s[rH]; s[rE] = s[rL]; s[rH] = v >> 8; s[rL] = v; return 4; case 0xfb: intm |= 0xc0; return 4; case 0xcc: return call(fetch16(), (s[rF] & FLAGZ) != 0); case 0xdc: return call(fetch16(), (s[rF] & FLAGC) != 0); case 0xec: return call(fetch16(), (s[rF] & FLAGV) != 0); case 0xfc: return call(fetch16(), (s[rF] & FLAGS) != 0); case 0xcd: return call(fetch16(), 1); case 0xdd: return index(0); case 0xed: return ed(); case 0xfd: return index(1); case 0xce: return alu(1, 8); case 0xde: return alu(3, 8); case 0xee: return alu(5, 8); case 0xfe: return alu(7, 8); case 0xcf: return call(0x08, 1); case 0xdf: return call(0x18, 1); case 0xef: return call(0x28, 1); case 0xff: return call(0x38, 1); } sysfatal("undefined z80 opcode %#.2x at pc=%#.4x", op, scurpc); return 0; }