ref: 7ab86494986671bf38464435f57fb6f925ce8632
dir: /sys/src/games/snes/ppu.c/
#include <u.h> #include <libc.h> #include <thread.h> #include "dat.h" #include "fns.h" int ppux, ppuy, rx; static u8int mode, bright, pixelpri[2], hires; static u32int pixelcol[2]; u16int vtime = 0x1ff, htime = 0x1ff, subcolor; uchar pic[256*239*2*3]; u16int hofs[5], vofs[5]; s16int m7[6]; enum { M7A, M7B, M7C, M7D, M7X, M7Y }; enum { OBJ = 4, COL = 5, OBJNC = 8 }; static u16int darken(u16int v) { u8int r, g, b; r = (v >> 10) & 0x1f; g = (v >> 5) & 0x1f; b = v & 0x1f; r = r * bright / 15; g = g * bright / 15; b = b * bright / 15; return r << 10 | g << 5 | b; } static void pixeldraw(int x, int y, u16int v, int s) { uchar *p; u16int *q; union { u16int w; u8int b[2]; } u; if(bright != 0xf && s >= 0) v = darken(v); if(scale == 1){ p = pic + (x + y * 256) * 2; p[0] = v; p[1] = v >> 8; return; } u.b[0] = v; u.b[1] = v >> 8; if(scale == 2){ q = (u16int*)pic + (x + y * 256) * 2; if(s < 1) q[0] = u.w; q[1] = u.w; }else{ q = (u16int*)pic + (x + y * 256) * 3; q[0] = u.w; q[1] = u.w; q[2] = u.w; } } static int window(int n) { int a, w1, w2; a = reg[0x2123 + (n >> 1)]; if((n & 1) != 0) a >>= 4; if((a & (WIN1|WIN2)) == 0) return 0; w1 = rx >= reg[0x2126] && rx <= reg[0x2127]; w2 = rx >= reg[0x2128] && rx <= reg[0x2129]; if((a & INVW1) != 0) w1 = !w1; if((a & INVW2) != 0) w2 = !w2; if((a & (WIN1|WIN2)) != (WIN1|WIN2)) return (a & WIN1) != 0 ? w1 : w2; a = reg[0x212a + (n >> 2)] >> ((n & 3) << 1); switch(a & 3){ case 1: return w1 & w2; case 2: return w1 ^ w2; case 3: return w1 ^ w2 ^ 1; } return w1 | w2; } static void npixel(int n, int v, int pri) { int a; a = 1<<n; if((reg[TM] & a) != 0 && pri > pixelpri[0] && ((reg[TMW] & a) == 0 || !window(n))){ pixelcol[0] = v; pixelpri[0] = pri; } if((reg[TS] & a) != 0 && pri > pixelpri[1] && ((reg[TSW] & a) == 0 || !window(n))){ pixelcol[1] = v; pixelpri[1] = pri; } } static void spixel(int n, int v, int pri) { int a; a = 1<<n; if((reg[TS] & a) != 0 && pri > pixelpri[1] && ((reg[TSW] & a) == 0 || !window(n))){ pixelcol[1] = v; pixelpri[1] = pri; } } static void mpixel(int n, int v, int pri) { int a; a = 1<<n; if((reg[TM] & a) != 0 && pri > pixelpri[0] && ((reg[TMW] & a) == 0 || !window(n))){ pixelcol[0] = v; pixelpri[0] = pri; } } static void (*pixel)(int, int, int) = npixel; static u16int tile(int n, int tx, int ty) { int a; u16int ta; u16int t; a = reg[0x2107 + n]; ta = ((a & ~3) << 9) + ((tx & 0x1f) << 1) + ((ty & 0x1f) << 6); if((a & 1) != 0) ta += (tx & 0x20) << 6; if((a & 2) != 0) ta += (ty & 0x20) << (6 + (a & 1)); t = vram[ta++]; return t | vram[ta] << 8; } static void chr(int n, int nb, int w, int h, u16int t, int x, int y, u32int c[]) { u16int a; if(w == 16) t += (x >> 3 ^ t >> 14) & 1; if(h == 16){ if(y >= 8){ t += (~t >> 11) & 16; y -= 8; }else t += (t >> 11) & 16; } if((t & 0x8000) != 0) y = 7 - y; a = reg[0x210b + (n >> 1)]; if((n & 1) != 0) a >>= 4; else a &= 0xf; a = (a << 13) + (t & 0x3ff) * 8 * nb + y * 2; c[0] = vram[a++]; c[0] |= vram[a] << 8; if(nb != 2){ a += 15; c[0] |= vram[a++] << 16; c[0] |= vram[a] << 24; if(nb == 8){ a += 15; c[1] = vram[a++]; c[1] |= vram[a] << 8; a += 15; c[1] |= vram[a++] << 16; c[1] |= vram[a] << 24; } } } static int palette(int n, int p) { switch(mode){ case 0: return p << 2 | n << 5; case 1: if(n >= 2) return p << 2; case 2: case 6: return p << 4; case 5: if(n == 0) return p << 4; return p << 2; case 3: if(n != 0) return p << 4; case 4: if(n != 0) return p << 2; if((reg[CGWSEL] & DIRCOL) != 0) return 0x10000; } return 0; } static void shift(u32int *c, int nb, int n, int d) { if(d){ c[0] >>= n; if(nb == 8) c[1] >>= n; }else{ c[0] <<= n; if(nb == 8) c[1] <<= n; } } static u8int bgpixel(u32int *c, int nb, int d) { u8int v; if(d){ v = c[0] & 1 | c[0] >> 7 & 2; if(nb != 2){ v |= c[0] >> 14 & 4 | c[0] >> 21 & 8; if(nb == 8){ v |= c[1] << 4 & 16 | c[1] >> 3 & 32 | c[1] >> 10 & 64 | c[1] >> 17 & 128; c[1] >>= 1; } } c[0] >>= 1; }else{ v = c[0] >> 7 & 1 | c[0] >> 14 & 2; if(nb != 2){ v |= c[0] >> 21 & 4 | c[0] >> 28 & 8; if(nb == 8){ v |= c[1] >> 3 & 16 | c[1] >> 10 & 32 | c[1] >> 17 & 64 | c[1] >> 24 & 128; c[1] <<= 1; } } c[0] <<= 1; } return v; } static struct bgctxt { u8int w, h, wsh, hsh, nb, pri[2]; u16int tx, ty, tnx, tny; u16int t; u32int c[2]; int pal; u8int msz, mv, mx; u16int otx, oty, otny; } bgctxts[4]; static void bginit(int n, int nb, int prilo, int prihi) { struct bgctxt *p; int sx, sy; p = bgctxts + n; p->hsh = ((reg[BGMODE] & (1<<(4+n))) != 0) ? 4 : 3; p->wsh = mode >= 5 ? 4 : p->hsh; p->h = 1<<p->hsh; p->w = 1<<p->wsh; p->nb = nb; p->pri[0] = prilo; p->pri[1] = prihi; sx = hofs[n]; sy = vofs[n] + ppuy; if(reg[MOSAIC] != 0 && (reg[MOSAIC] & (1<<n)) != 0){ p->msz = (reg[MOSAIC] >> 4) + 1; if(p->msz != 1){ sx -= p->mx = sx % p->msz; sy -= sy % p->msz; } }else p->msz = 1; if(mode >= 5) sx <<= 1; redo: p->tx = sx >> p->wsh; p->tnx = sx & (p->w - 1); p->ty = sy >> p->hsh; p->tny = sy & (p->h - 1); p->t = tile(n, p->tx, p->ty); chr(n, nb, p->w, p->h, p->t, p->tnx, p->tny, p->c); p->pal = palette(n, p->t >> 10 & 7); if((p->tnx & 7) != 0) shift(p->c, nb, p->tnx & 7, p->t & 0x4000); if(p->msz != 1 && p->mx != 0 && sx % p->msz == 0){ p->mv = bgpixel(p->c, nb, p->t & 0x4000); if(p->tnx + p->mx >= 8){ sx += p->mx; goto redo; }else if(p->mx > 1) shift(p->c, nb, p->mx - 1, p->t & 0x4000); } } static void bg(int n) { struct bgctxt *p; u8int v; p = bgctxts + n; v = bgpixel(p->c, p->nb, p->t & 0x4000); if(p->msz != 1) if(p->mx++ == 0) p->mv = v; else{ if(p->mx == p->msz) p->mx = 0; v = p->mv; } if(v != 0) pixel(n, p->pal + v, p->pri[(p->t & 0x2000) != 0]); if(++p->tnx == p->w){ p->tx++; p->tnx = 0; p->t = tile(n, p->tx, p->ty); p->pal = palette(n, p->t >> 10 & 7); } if((p->tnx & 7) == 0) chr(n, p->nb, p->w, p->h, p->t, p->tnx, p->tny, p->c); } static void optinit(void) { struct bgctxt *p; p = bgctxts + 2; p->hsh = (reg[BGMODE] & (1<<6)) != 0 ? 4 : 3; p->wsh = mode >= 5 ? 4 : p->hsh; p->w = 1<<p->wsh; p->h = 1<<p->hsh; p->tnx = hofs[2] & (p->w - 1); p->tx = hofs[2] >> p->wsh; bgctxts[0].otx = bgctxts[1].otx = 0xffff; bgctxts[0].oty = bgctxts[0].ty; bgctxts[0].otny = bgctxts[0].tny; bgctxts[1].oty = bgctxts[1].ty; bgctxts[1].otny = bgctxts[1].tny; } static void opt(void) { struct bgctxt *p; u16int hval, vval; int sx, sy; p = bgctxts + 2; if(++p->tnx == p->w){ if(mode == 4){ hval = tile(2, p->tx, vofs[2] >> p->hsh); if((hval & 0x8000) != 0){ vval = hval; hval = 0; }else vval = 0; }else{ hval = tile(2, p->tx, vofs[2] >> p->hsh); vval = tile(2, p->tx, (vofs[2]+8) >> p->hsh); } sx = (rx & ~7) + (hval & 0x1ff8); sy = ppuy + (vval & 0x1fff); if((vval & 0x2000) != 0){ bgctxts[0].oty = sy >> bgctxts[0].hsh; bgctxts[0].otny = sy & (bgctxts[0].h - 1); }else{ bgctxts[0].oty = bgctxts[0].ty; bgctxts[0].otny = bgctxts[0].tny; } if((vval & 0x4000) != 0){ bgctxts[1].oty = sy >> bgctxts[1].hsh; bgctxts[1].otny = sy & (bgctxts[1].h - 1); }else{ bgctxts[1].oty = bgctxts[1].ty; bgctxts[1].otny = bgctxts[1].tny; } if((hval & 0x2000) != 0) bgctxts[0].otx = sx >> bgctxts[0].wsh; else bgctxts[0].otx = 0xffff; if((hval & 0x4000) != 0) bgctxts[1].otx = sx >> bgctxts[1].wsh; else bgctxts[1].otx = 0xffff; p->tnx = 0; p->tx++; } } static void bgopt(int n) { struct bgctxt *p; u8int v; p = bgctxts + n; v = bgpixel(p->c, p->nb, p->t & 0x4000); if(p->msz != 1) if(p->mx++ == 0) p->mv = v; else{ if(p->mx == p->msz) p->mx = 0; v = p->mv; } if(v != 0) pixel(n, p->pal + v, p->pri[(p->t & 0x2000) != 0]); if(++p->tnx == p->w){ p->tx++; p->tnx = 0; } if((p->tnx & 7) == 0){ p->t = tile(n, p->otx == 0xffff ? p->tx : p->otx, p->oty); p->pal = palette(n, p->t >> 10 & 7); chr(n, p->nb, p->w, p->h, p->t, p->tnx, p->otny, p->c); } } struct bg7ctxt { int x, y, x0, y0; u8int msz, mx, mv; } b7[2]; void calc7(void) { s16int t; if((reg[0x2105] & 7) != 7) return; t = hofs[4] - m7[M7X]; if((t & 0x2000) != 0) t |= ~0x3ff; else t &= 0x3ff; b7->x0 = (t * m7[M7A]) & ~63; b7->y0 = (t * m7[M7C]) & ~63; t = vofs[4] - m7[M7Y]; if((t & 0x2000) != 0) t |= ~0x3ff; else t &= 0x3ff; b7->x0 += (t * m7[M7B]) & ~63; b7->y0 += (t * m7[M7D]) & ~63; b7->x0 += m7[M7X] << 8; b7->y0 += m7[M7Y] << 8; } static void bg7init(int n) { u8int m, y; struct bg7ctxt *p; p = b7 + n; m = reg[M7SEL]; y = ppuy; p->msz = 1; if((reg[MOSAIC] & 1) != 0){ p->msz = (reg[MOSAIC] >> 4) + 1; if(p->msz != 1) y -= y % p->msz; } if(n == 1) if((reg[MOSAIC] & 2) != 0) p->msz = (reg[MOSAIC] >> 4) + 1; else p->msz = 1; if((m & 2) != 0) y = 255 - y; p->x = b7->x0 + ((m7[M7B] * y) & ~63); p->y = b7->y0 + ((m7[M7D] * y) & ~63); if((m & 1) != 0){ p->x += 255 * m7[M7A]; p->y += 255 * m7[M7C]; } } static void bg7(int n) { u16int x, y; u8int m, v, t; struct bg7ctxt *p; p = b7 + n; m = reg[M7SEL]; x = p->x >> 8; y = p->y >> 8; if((m & 0x80) == 0){ x &= 1023; y &= 1023; }else if(x > 1023 || y > 1023){ if((m & 0x40) != 0){ t = 0; goto lookup; } v = 0; goto end; } t = vram[x >> 2 & 0xfe | y << 5 & 0x7f00]; lookup: v = vram[t << 7 | y << 4 & 0x70 | x << 1 & 0x0e | 1]; end: if(p->msz != 1){ if(p->mx == 0) p->mv = v; else v = p->mv; if(++p->mx == p->msz) p->mx = 0; } if(n == 1){ if((v & 0x7f) != 0) if((v & 0x80) != 0) pixel(1, v & 0x7f, 0x71); else pixel(1, v, 0x11); }else if(v != 0) pixel(0, v, 0x40); if((m & 1) != 0){ p->x -= m7[M7A]; p->y -= m7[M7C]; }else{ p->x += m7[M7A]; p->y += m7[M7C]; } } static void bgsinit(void) { static int bitch[8]; pixel = npixel; switch(mode){ case 0: bginit(0, 2, 0x80, 0xb0); bginit(1, 2, 0x71, 0xa1); bginit(2, 2, 0x22, 0x52); bginit(3, 2, 0x13, 0x43); break; case 1: bginit(0, 4, 0x80, 0xb0); bginit(1, 4, 0x71, 0xa1); bginit(2, 2, 0x12, (reg[BGMODE] & 8) != 0 ? 0xd2 : 0x42); break; case 2: bginit(0, 4, 0x40, 0xa0); bginit(1, 4, 0x11, 0x71); optinit(); break; case 3: bginit(0, 8, 0x40, 0xa0); bginit(1, 4, 0x11, 0x71); break; case 4: bginit(0, 8, 0x40, 0xa0); bginit(1, 2, 0x11, 0x71); optinit(); break; case 5: bginit(0, 4, 0x40, 0xa0); bginit(1, 2, 0x11, 0x71); break; case 6: bginit(0, 4, 0x40, 0xa0); optinit(); break; case 7: bg7init(0); if((reg[SETINI] & EXTBG) != 0) bg7init(1); break; default: bgctxts[0].w = bgctxts[1].w = 0; if(bitch[mode]++ == 0) print("bg mode %d not implemented\n", mode); } } static void bgs(void) { switch(mode){ case 0: bg(0); bg(1); bg(2); bg(3); break; case 1: bg(0); bg(1); bg(2); break; case 2: case 4: opt(); bgopt(0); bgopt(1); break; case 3: bg(0); bg(1); break; case 5: pixel = spixel; bg(0); bg(1); pixel = mpixel; bg(0); bg(1); pixel = npixel; break; case 6: opt(); pixel = spixel; bgopt(0); pixel = mpixel; bgopt(0); pixel = npixel; break; case 7: bg7(0); if((reg[SETINI] & EXTBG) != 0) bg7(1); break; } } static void sprites(void) { static struct { short x; u8int y, i, c, sx, sy; u16int t0, t1; } s[32], *sp; static struct { short x; u8int sx, i, c, pal, pri; u32int *ch; } t[32], *tp; static u32int ch[34]; static u8int *p, q; static int n, m; static int *sz; static int szs[] = { 8, 8, 16, 16, 8, 8, 32, 32, 8, 8, 64, 64, 16, 16, 32, 32, 16, 16, 64, 64, 32, 32, 64, 64, 16, 32, 32, 64, 16, 32, 32, 32 }; static u16int base[2]; u8int dy, v, col, pri0, pri1, prio; u16int a; u32int w, *cp; int i, nt, dx; if(rx == 0){ n = 0; sp = s; sz = szs + ((reg[OBSEL] & 0xe0) >> 3); base[0] = (reg[OBSEL] & 0x07) << 14; base[1] = base[0] + (((reg[OBSEL] & 0x18) + 8) << 10); } if((rx & 1) == 0){ p = oam + 2 * rx; if(p[1] == 0xf0) goto nope; q = (oam[512 + (rx >> 3)] >> (rx & 6)) & 3; dy = ppuy - p[1]; sp->sx = sz[q & 2]; sp->sy = sz[(q & 2) + 1]; if(dy >= sp->sy) goto nope; sp->x = p[0]; if((q & 1) != 0) sp->x |= 0xff00; if(sp->x <= -(short)sp->sx && sp->x != -256) goto nope; if(n == 32){ reg[0x213e] |= 0x40; goto nope; } sp->i = rx >> 1; sp->y = p[1]; sp->c = p[3]; sp->t0 = p[2] << 5; sp->t1 = base[sp->c & 1]; sp++; n++; } nope: if(ppuy != 0){ col = 0; pri0 = 0; pri1 = 128; if((reg[OAMADDH] & 0x80) != 0) prio = oamaddr >> 2; else prio = 0; for(i = 0, tp = t; i < m; i++, tp++){ dx = rx - tp->x; if(dx < 0 || dx >= tp->sx) continue; w = *tp->ch; if((tp->c & 0x40) != 0){ v = w & 1 | w >> 7 & 2 | w >> 14 & 4 | w >> 21 & 8; *tp->ch = w >> 1; }else{ v = w >> 7 & 1 | w >> 14 & 2 | w >> 21 & 4 | w >> 28 & 8; *tp->ch = w << 1; } if((dx & 7) == 7) tp->ch++; nt = (tp->i - prio) & 0x7f; if(v != 0 && nt < pri1){ col = tp->pal + v; pri0 = tp->pri; pri1 = nt; } } if(col > 0) pixel(OBJ, col, pri0); } if(rx == 255){ cp = ch; m = n; for(sp = s + n - 1, tp = t + n - 1; sp >= s; sp--, tp--){ tp->x = sp->x; tp->sx = 0; tp->c = sp->c; tp->pal = 0x80 | sp->c << 3 & 0x70; tp->pri = 3 * (0x10 + (sp->c & 0x30)); if((tp->c & 8) != 0) tp->pri |= OBJ; else tp->pri |= OBJNC; tp->ch = cp; tp->i = sp->i; nt = sp->sx >> 3; dy = ppuy - sp->y; if((sp->c & 0x80) != 0) dy = sp->sy - 1 - dy; a = sp->t0 | (dy & 7) << 1; if(dy >= 8) a += (dy & ~7) << 6; if(sp->x < 0 && (i = (-sp->x >> 3)) != 0){ if((sp->c & 0x40) != 0) a -= i << 5; else a += i << 5; nt -= i; tp->sx += i << 3; } if((sp->c & 0x40) != 0){ a += sp->sx * 4; for(i = 0; i < nt; i++){ if(cp < ch + nelem(ch)){ w = vram[sp->t1 | (a -= 16) & 0x1fff] << 16; w |= vram[sp->t1 | (a + 1) & 0x1fff] << 24; w |= vram[sp->t1 | (a -= 16) & 0x1fff] << 0; w |= vram[sp->t1 | (a + 1) & 0x1fff] << 8; *cp++ = w; tp->sx += 8; }else reg[0x213e] |= 0x80; } }else for(i = 0; i < nt; i++){ if(cp < ch + nelem(ch)){ w = vram[sp->t1 | a & 0x1fff]; w |= vram[sp->t1 | ++a & 0x1fff] << 8; w |= vram[sp->t1 | (a += 15) & 0x1fff] << 16; w |= vram[sp->t1 | ++a & 0x1fff] << 24; *cp++ = w; tp->sx += 8; a += 15; }else reg[0x213e] |= 0x80; } if(sp->x < 0 && (i = (-sp->x) & 7) != 0) if((sp->c & 0x40) != 0) *tp->ch >>= i; else *tp->ch <<= i; } } } static u16int colormath(int n) { u16int v, w, r, g, b; u8int m, m2, div; int cw; m = reg[CGWSEL]; m2 = reg[CGADSUB]; cw = -1; switch(m >> 6){ default: v = 1; break; case 1: v = cw = window(COL); break; case 2: v = !(cw = window(COL)); break; case 3: v = 0; break; } if(v){ if((pixelcol[n] & 0x10000) != 0) v = pixelcol[n]; else v = cgram[pixelcol[n] & 0xff]; } if((m2 & (1 << (pixelpri[n] & 0xf))) == 0) return v; switch((m >> 4) & 3){ case 0: break; case 1: if(cw < 0) cw = window(COL); if(!cw) return v; break; case 2: if(cw < 0) cw = window(COL); if(cw) return v; break; default: return v; } div = (m2 & 0x40) != 0; if((m & 2) != 0){ if((pixelcol[1-n] & 0x10000) != 0) w = pixelcol[1-n]; else w = cgram[pixelcol[1-n] & 0xff]; div = div && (pixelpri[1-n] & 0xf) != COL; }else w = subcolor; if((m2 & 0x80) != 0){ r = (v & 0x7c00) - (w & 0x7c00); g = (v & 0x03e0) - (w & 0x03e0); b = (v & 0x001f) - (w & 0x001f); if(r > 0x7c00) r = 0; if(g > 0x03e0) g = 0; if(b > 0x001f) b = 0; if(div){ r = (r >> 1) & 0xfc00; g = (g >> 1) & 0xffe0; b >>= 1; } return r | g | b; }else{ r = (v & 0x7c00) + (w & 0x7c00); g = (v & 0x03e0) + (w & 0x03e0); b = (v & 0x001f) + (w & 0x001f); if(div){ r = (r >> 1) & 0xfc00; g = (g >> 1) & 0xffe0; b >>= 1; } if(r > 0x7c00) r = 0x7c00; if(g > 0x03e0) g = 0x03e0; if(b > 0x001f) b = 0x001f; return r | g | b; } } void ppustep(void) { int yvbl; mode = reg[BGMODE] & 7; bright = reg[INIDISP] & 0xf; hires = mode >= 5 && mode < 7 || (reg[SETINI] & 8) != 0; yvbl = (reg[SETINI] & OVERSCAN) != 0 ? 0xf0 : 0xe1; if(ppux >= XLEFT && ppux <= XRIGHT && ppuy < 0xf0){ rx = ppux - XLEFT; if(ppuy < yvbl && (reg[INIDISP] & 0x80) == 0){ pixelcol[0] = 0; pixelpri[0] = COL; pixelcol[1] = 0x10000 | subcolor; pixelpri[1] = COL; bgs(); sprites(); if(ppuy != 0) if(hires){ pixeldraw(rx, ppuy - 1, colormath(1), 0); pixeldraw(rx, ppuy - 1, colormath(0), 1); }else pixeldraw(rx, ppuy - 1, colormath(0), 0); }else if(ppuy != 0) pixeldraw(rx, ppuy - 1, ppuy >= yvbl ? 0x6739 : 0, -1); } if(ppux == 134) cpupause = 1; if(ppux == 0x116 && ppuy <= yvbl) hdma |= reg[0x420c]; if((reg[NMITIMEN] & HCNTIRQ) != 0 && htime+4 == ppux && ((reg[NMITIMEN] & VCNTIRQ) == 0 || vtime == ppuy)) irq |= IRQPPU; if(++ppux >= 340){ ppux = 0; if(++ppuy >= 262){ ppuy = 0; reg[RDNMI] &= ~VBLANK; reg[0x213e] = 1; reg[0x213f] ^= 0x80; hdma = reg[0x420c]<<8; flush(); } if(ppuy < yvbl) bgsinit(); if(ppuy == yvbl){ reg[RDNMI] |= VBLANK; if((reg[NMITIMEN] & VBLANK) != 0) nmi = 2; if((reg[INIDISP] & 0x80) == 0) oamaddr = reg[0x2102] << 1 | (reg[0x2103] & 1) << 9; if((reg[NMITIMEN] & AUTOJOY) != 0){ memwrite(0x4016, 1); memwrite(0x4016, 0); reg[0x4218] = keylatch >> 16; reg[0x4219] = keylatch >> 24; keylatch = keylatch << 16 | 0xffff; } } if((reg[NMITIMEN] & (HCNTIRQ|VCNTIRQ)) == VCNTIRQ && vtime == ppuy) irq |= IRQPPU; } }