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added games/c64

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This commit is contained in:
aiju 2015-02-07 18:03:17 +01:00
parent 8ac5227a36
commit f6eacf471e
10 changed files with 1676 additions and 0 deletions
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sys/lib/c64/basic.bin Normal file
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sys/lib/c64/crom.bin Normal file
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sys/lib/c64/kernal.bin Normal file
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sys/src/games/c64/c64.c Normal file
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#include <u.h>
#include <libc.h>
#include <thread.h>
#include <draw.h>
#include <mouse.h>
#include <keyboard.h>
#include "dat.h"
#include "fns.h"
char *bindir = "/sys/lib/c64";
Image *tmp, *bg, *red;
Rectangle picr, progr;
Mousectl *mc;
QLock pauselock;
int paused, scale;
u8int *rom;
int nrom;
u64int keys;
u16int joys;
uchar *tape, tapever, tapeplay;
ulong tapelen;
int joymode;
void
progress(int a, int b)
{
static int cur;
int w;
if(b == 0 || a == 0){
if(cur != 0){
draw(screen, progr, bg, nil, ZP);
cur = 0;
}
return;
}
w = a * Dx(progr) / b;
if(cur == w)
return;
draw(screen, Rect(progr.min.x, progr.min.y, progr.min.x + w, progr.max.y), red, nil, ZP);
cur = w;
}
static void
loadsys(char *name, u8int *p, int n)
{
static char buf[256];
int fd;
snprint(buf, sizeof(buf), "%s/%s", bindir, name);
fd = open(buf, OREAD);
if(fd < 0)
sysfatal("open: %r");
if(readn(fd, p, n) < n)
sysfatal("readn: %r");
close(fd);
}
static void
loadrom(char *name)
{
int fd;
fd = open(name, OREAD);
if(fd < 0)
sysfatal("open: %r");
nrom = seek(fd, 0, 2);
if(nrom > 4096)
sysfatal("large ROM not supported");
if((nrom & nrom-1) != 0)
sysfatal("non-power-of-two ROM size");
rom = malloc(nrom);
if(rom == nil)
sysfatal("malloc: %r");
pread(fd, rom, nrom, 0);
close(fd);
}
static void
loadcart(char *name)
{
int fd;
u16int t, l;
u8int buf[80];
fd = open(name, OREAD);
if(fd < 0)
sysfatal("open: %r");
read(fd, buf, 80);
if(memcmp(buf, "C64 CARTRIDGE ", 16) != 0)
sysfatal("not a c64 cartridge");
t = buf[0x16] << 8 | buf[0x17];
if(t != 0)
sysfatal("unsupported type %d", t);
if(buf[0x18] == 0) pla &= ~EXROM;
if(buf[0x19] == 0) pla &= ~GAME;
t = buf[0x4c] << 8 | buf[0x4d];
if(t < 0x8000 || t >= 0xc000 && t < 0xe000)
sysfatal("odd starting address %x", t);
if(t >= 0xe000)
t -= 0x4000;
t -= 0x8000;
l = buf[0x4e] << 8 | buf[0x4f];
if(l + t > 16384)
sysfatal("cart too large");
read(fd, cart + t, l);
close(fd);
}
static void
loadtape(char *name)
{
int fd;
uchar buf[20];
fd = open(name, OREAD);
if(fd < 0)
sysfatal("open: %r");
read(fd, buf, 20);
if(memcmp(buf, "C64-TAPE-RAW", 12) != 0)
sysfatal("not a c64 raw tape");
tapever = buf[12];
if(tapever > 1)
sysfatal("unsupported tape version %d", tapever);
tapelen = buf[16] | buf[17] << 8 | buf[18] << 16 | buf[19] << 24;
tape = malloc(tapelen);
readn(fd, tape, tapelen);
close(fd);
}
static void
keyproc(void *)
{
int fd, i, setnmi;
u16int j;
u64int k;
static Rune keymap[64] = {
Kbs, '\n', Kleft, KF|7, KF|1, KF|3, KF|5, Kup,
'3', 'w', 'a', '4', 'z', 's', 'e', Kshift,
'5', 'r', 'd', '6', 'c', 'f', 't', 'x',
'7', 'y', 'g', '8', 'b', 'h', 'u', 'v',
'9', 'i', 'j', '0', 'm', 'k', 'o', 'n',
'\'', 'p', 'l', '-', '.', ':', '@', ',',
'[', '*', ';', Khome, Kalt, '=', ']', '/',
'1', Kins, '\t', '2', ' ', Kctl, 'q', Kdel
};
static char buf[256];
char *s;
Rune r;
fd = open("/dev/kbd", OREAD);
if(fd < 0)
sysfatal("open: %r");
for(;;){
if(read(fd, buf, sizeof(buf) - 1) <= 0)
sysfatal("read /dev/kbd: %r");
if(buf[0] == 'c'){
if(utfrune(buf, Kend)){
close(fd);
threadexitsall(nil);
}
if(utfrune(buf, KF|12))
trace ^= 1;
}
if(buf[0] != 'k' && buf[0] != 'K')
continue;
s = buf + 1;
j = 0;
k = 0;
setnmi = 0;
while(*s != 0){
s += chartorune(&r, s);
switch(r){
case Kend: close(fd); threadexitsall(nil);
case Kesc:
if(paused)
qunlock(&pauselock);
else
qlock(&pauselock);
paused = !paused;
break;
case '`':
setnmi = 1;
break;
case Kleft: if(joymode) j |= 1<<2+5*(joymode-1); break;
case Kright: if(joymode) j |= 1<<3+5*(joymode-1); break;
case Kup: if(joymode) j |= 1<<0+5*(joymode-1); break;
case Kdown: if(joymode) j |= 1<<1+5*(joymode-1); break;
case Kctl: if(joymode) j |= 1<<4+5*(joymode-1); break;
}
for(i = 0; i < 64; i++)
if(keymap[i] == r)
k |= 1ULL<<i;
}
if(setnmi)
nmi |= IRQRESTORE;
else
nmi &= ~IRQRESTORE;
keys = k;
joys = j;
}
}
static void
screeninit(void)
{
Point p, q;
p = divpt(addpt(screen->r.min, screen->r.max), 2);
picr = (Rectangle){subpt(p, Pt(picw/2*scale, pich/2*scale)), addpt(p, Pt(picw/2*scale, pich/2*scale))};
p.y += pich*scale*3/4;
q = Pt(Dx(screen->r) * 2/5, 8);
progr = (Rectangle){subpt(p, q), addpt(p, q)};
tmp = allocimage(display, Rect(0, 0, picw*scale, scale > 1 ? 1 : pich), XRGB32, 1, 0);
bg = allocimage(display, Rect(0, 0, 1, 1), screen->chan, 1, 0xCCCCCCFF);
red = allocimage(display, Rect(0, 0, 1, 1), screen->chan, 1, 0xFF0000FF);
draw(screen, screen->r, bg, nil, ZP);
}
static void
usage(void)
{
fprint(2, "usage: %s [ -23a ] [ rom ]\n", argv0);
exits("usage");
}
void
threadmain(int argc, char **argv)
{
scale = 1;
memreset();
ARGBEGIN {
case '2':
scale = 2;
break;
case '3':
scale = 3;
break;
case 'c':
loadcart(EARGF(usage()));
break;
case 't':
loadtape(EARGF(usage()));
break;
case 'N':
region = NTSC0;
break;
case 'p':
region = PAL;
break;
case 'd':
bindir = strdup(EARGF(usage()));
break;
default:
usage();
} ARGEND;
if(argc >= 2)
usage();
loadsys("kernal.bin", krom, 8192);
loadsys("basic.bin", brom, 8192);
loadsys("crom.bin", crom, 4096);
vicreset();
if(initdraw(nil, nil, nil) < 0)
sysfatal("initdraw: %r");
mc = initmouse(nil, screen);
if(mc == nil)
sysfatal("initmouse: %r");
screeninit();
proccreate(keyproc, nil, mainstacksize);
nmien = IRQRESTORE;
pc = memread(0xFFFC) | memread(0xFFFD) << 8;
rP = FLAGI;
for(;;){
if(paused){
qlock(&pauselock);
qunlock(&pauselock);
}
step();
}
}
static void
menu(void)
{
enum { JOY, TAPE };
static char joystr[32] = "joy: none";
static char tapestr[32] = "tape: play";
static char *items[] = {
[JOY] joystr,
[TAPE] tapestr,
nil
};
static Menu m = {
items, nil, 0
};
switch(menuhit(3, mc, &m, nil)){
case JOY:
joymode = (joymode + 1) % 3;
if(joymode == 0)
strcpy(joystr, "joy: none");
else
sprint(joystr, "joy: %d", joymode);
break;
case TAPE:
tapeplay ^= 1;
if(tapeplay == 0){
strcpy(tapestr, "tape: play");
progress(0, 0);
}else
strcpy(tapestr, "tape: stop");
break;
}
}
void
flush(void)
{
extern u8int pic[];
// vlong new, diff;
// static vlong old, delta;
if(nbrecvul(mc->resizec) > 0){
if(getwindow(display, Refnone) < 0)
sysfatal("resize failed: %r");
screeninit();
}
while(nbrecv(mc->c, &mc->Mouse) > 0)
if((mc->buttons & 4) != 0)
menu();
if(scale == 1){
loadimage(tmp, tmp->r, pic, picw*pich*4);
draw(screen, picr, tmp, nil, ZP);
}else{
Rectangle r;
uchar *s;
int w;
s = pic;
r = picr;
w = picw*4*scale;
while(r.min.y < picr.max.y){
loadimage(tmp, tmp->r, s, w);
s += w;
r.max.y = r.min.y+scale;
draw(screen, r, tmp, nil, ZP);
r.min.y = r.max.y;
}
}
flushimage(display, 1);
/*
if(audioout() < 0){
new = nsec();
diff = 0;
if(old != 0){
diff = BILLION/60 - (new - old) - delta;
if(diff >= MILLION)
sleep(diff/MILLION);
}
old = nsec();
if(diff != 0){
diff = (old - new) - (diff / MILLION) * MILLION;
delta += (diff - delta) / 100;
}
}
*/
}

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sys/src/games/c64/cpu.c Normal file
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#include <u.h>
#include <libc.h>
#include "dat.h"
#include "fns.h"
u16int pc, curpc;
u8int rA, rX, rY, rS, rP;
int nrdy, irq, nmi, nmi0, irqen, nmien;
static u8int
fetch8(void)
{
return memread(pc++);
}
static u16int
fetch16(void)
{
u16int r;
r = memread(pc++);
r |= memread(pc++) << 8;
return r;
}
static void
push8(u8int v)
{
memwrite(0x100 | rS--, v);
}
static void
push16(u16int v)
{
memwrite(0x100 | rS--, v >> 8);
memwrite(0x100 | rS--, v);
}
static u8int
pop8(void)
{
return memread(0x100 | ++rS);
}
static u16int
pop16(void)
{
u16int v;
v = memread(0x100 | ++rS);
v |= memread(0x100 | ++rS) << 8;
return v;
}
#define imm() fetch8()
#define zp() memread(fetch8())
#define zpX() memread(azpX(rX))
#define zpY() memread(azpX(rY))
#define abso() memread(fetch16())
#define absX() memread(aabsX(rX, 0))
#define absY() memread(aabsX(rY, 0))
#define indX() memread(aindX())
#define indY() memread(aindY(0))
static u16int
azpX(u8int a)
{
u8int v;
v = fetch8();
memread(v);
return v + a;
}
static u16int
aabsX(u8int a, int wr)
{
u16int v, c;
v = fetch16();
c = (u8int)v + a & 0x100;
v += a;
if(c != 0 || wr)
memread(v - c);
return v;
}
static u16int
aindX(void)
{
u8int r;
u16int a;
r = fetch8();
memread(r);
r += rX;
a = memread(r++);
a |= memread(r) << 8;
return a;
}
static u16int
aindY(int wr)
{
u8int r;
u16int a, c;
r = fetch8();
a = memread(r++) + rY;
c = a & 0x100;
a += memread(r) << 8;
if(c != 0 || wr)
memread(a - c);
return a;
}
static void
adc(u8int d)
{
int r;
if((rP & FLAGD) != 0){
r = (rA & 0xf) + (d & 0xf) + (rP & FLAGC);
if(r > 0x09)
r += 0x06;
if(r > 0x1f)
r -= 0x10;
r += (rA & 0xf0) + (d & 0xf0);
}else
r = rA + d + (rP & FLAGC);
rP &= ~(FLAGN | FLAGZ | FLAGV | FLAGC);
if((~(rA ^ d) & (rA ^ r)) & 0x80) rP |= FLAGV;
if((rP & FLAGD) != 0 && r > 0x9f)
r += 0x60;
if(r > 0xFF) rP |= FLAGC;
if(r & 0x80) rP |= FLAGN;
rA = r;
if(rA == 0) rP |= FLAGZ;
}
static u8int
nz(u8int d)
{
rP &= ~(FLAGN | FLAGZ);
if(d & 0x80) rP |= FLAGN;
if(d == 0) rP |= FLAGZ;
return d;
}
static void
asl(u16int a)
{
u8int v;
rP &= ~(FLAGN | FLAGZ | FLAGC);
v = memread(a);
memwrite(a, v);
if(v & 0x80) rP |= FLAGC;
v <<= 1;
if(v == 0) rP |= FLAGZ;
if(v & 0x80) rP |= FLAGN;
memwrite(a, v);
}
static void
lsr(u16int a)
{
u8int v;
rP &= ~(FLAGN | FLAGZ | FLAGC);
v = memread(a);
memwrite(a, v);
rP |= v & 1;
v >>= 1;
if(v == 0) rP |= FLAGZ;
if(v & 0x80) rP |= FLAGN;
memwrite(a, v);
}
static void
branch(void)
{
s8int t;
u16int npc;
t = fetch8();
memread(pc);
npc = pc + t;
if((npc ^ pc) >> 8)
memread(pc & 0xff00 | npc & 0xff);
pc = npc;
}
static void
cmp(u8int a, u8int d)
{
rP &= ~(FLAGN | FLAGZ | FLAGC);
if(a == d) rP |= FLAGZ;
if(a >= d) rP |= FLAGC;
if((a - d) & 0x80) rP |= FLAGN;
}
static void
dec(u16int a)
{
u8int v;
v = memread(a);
memwrite(a, v);
memwrite(a, nz(v - 1));
}
static void
inc(u16int a)
{
u8int v;
v = memread(a);
memwrite(a, v);
v = nz(v + 1);
memwrite(a, v);
}
static void
rol(u16int a)
{
u8int v, b;
v = memread(a);
memwrite(a, v);
b = rP & FLAGC;
rP &= ~(FLAGC | FLAGN | FLAGZ);
if(v & 0x80) rP |= FLAGC;
v = (v << 1) | b;
if(v & 0x80) rP |= FLAGN;
if(v == 0) rP |= FLAGZ;
memwrite(a, v);
}
static void
ror(u16int a)
{
u8int v, b;
v = memread(a);
memwrite(a, v);
b = rP & FLAGC;
rP &= ~(FLAGC | FLAGN | FLAGZ);
rP |= v & 1;
v = (v >> 1) | (b << 7);
if(v & 0x80) rP |= FLAGN;
if(v == 0) rP |= FLAGZ;
memwrite(a, v);
}
static void
sbc(u8int d)
{
int r;
if((rP & FLAGD) != 0){
d = ~d;
r = (rA & 0xf) + (d & 0xf) + (rP & FLAGC);
if(r < 0x10) r -= 0x06;
if(r < 0) r += 0x10;
r += (rA & 0xf0) + (d & 0xf0);
}else
r = rA + (u8int)~d + (rP & FLAGC);
rP &= ~(FLAGZ | FLAGV | FLAGC | FLAGN);
if(((rA ^ d) & (rA ^ r)) & 0x80) rP |= FLAGV;
if(r > 0xFF) rP |= FLAGC;
else if((rP & FLAGD) != 0)
r -= 0x60;
rA = r;
if(rA == 0) rP |= FLAGZ;
if(rA & 0x80) rP |= FLAGN;
}
static void
interrupt(int nmi, int brk)
{
memread(pc);
if(brk)
pc++;
push16(pc);
push8(rP | 0x20 | (brk << 4));
pc = memread(0xFFFA | (!nmi << 2));
pc |= memread(0xFFFB | (!nmi << 2)) << 8;
rP |= FLAGI;
}
int trace;
void
step(void)
{
u8int op;
u16int a, v;
if(nrdy){
io();
return;
}
if((nmi & nmien) != 0 && (nmi0 & nmien) == 0){
nmi0 = nmi;
interrupt(1, 0);
return;
}
nmi0 = nmi;
if((irq & irqen) != 0 && (rP & FLAGI) == 0){
interrupt(0, 0);
return;
}
curpc = pc;
op = fetch8();
if(trace)
print("%.4x %.2x | %.2x %.2x %.2x | %.2x %.2x | %3d %3d %.6x %.6x\n", curpc, op, rA, rX, rY, rS, rP, ppux-3, ppuy, irq, nmi);
switch(op){
case 0x00: fetch8(); interrupt(0, 1); return;
case 0x01: nz(rA |= indX()); return;
case 0x05: nz(rA |= zp()); return;
case 0x06: asl(fetch8()); return;
case 0x08: memread(pc); push8(rP | 0x30); return;
case 0x09: nz(rA |= imm()); return;
case 0x0A:
rP &= ~(FLAGN | FLAGZ | FLAGC);
if(rA & 0x80) rP |= FLAGC;
rA <<= 1;
if(rA == 0) rP |= FLAGZ;
if(rA & 0x80) rP |= FLAGN;
memread(pc);
return;
case 0x0D: nz(rA |= abso()); return;
case 0x0E: asl(fetch16()); return;
case 0x10: if((rP & FLAGN) == 0) branch(); else fetch8(); return;
case 0x11: nz(rA |= indY()); return;
case 0x15: nz(rA |= zpX()); return;
case 0x16: asl(azpX(rX)); return;
case 0x18: rP &= ~FLAGC; memread(pc); return;
case 0x19: nz(rA |= absY()); return;
case 0x1D: nz(rA |= absX()); return;
case 0x1E: asl(aabsX(rX, 1)); return;
case 0x20: v = fetch8(); memread(rS|0x100); push16(pc); pc = fetch8() << 8 | v; return;
case 0x21: nz(rA &= indX()); return;
case 0x24:
a = memread(fetch8());
rP &= ~(FLAGN | FLAGZ | FLAGV);
rP |= a & 0xC0;
if((a & rA) == 0) rP |= FLAGZ;
return;
case 0x25: nz(rA &= zp()); return;
case 0x26: rol(fetch8()); return;
case 0x28: memread(pc); memread(0x100|rS); rP = pop8() & 0xcf; return;
case 0x29: nz(rA &= imm()); return;
case 0x2A:
a = rP & FLAGC;
rP &= ~(FLAGC | FLAGZ | FLAGN);
if(rA & 0x80) rP |= FLAGC;
rA = (rA << 1) | a;
if(rA & 0x80) rP |= FLAGN;
if(rA == 0) rP |= FLAGZ;
memread(pc);
return;
case 0x2C:
a = memread(fetch16());
rP &= ~(FLAGN | FLAGZ | FLAGV);
rP |= a & 0xC0;
if((a & rA) == 0) rP |= FLAGZ;
return;
case 0x2D: nz(rA &= abso()); return;
case 0x2E: rol(fetch16()); return;
case 0x30: if((rP & FLAGN) != 0) branch(); else fetch8(); return;
case 0x31: nz(rA &= indY()); return;
case 0x35: nz(rA &= zpX()); return;
case 0x36: rol(azpX(rX)); return;
case 0x38: rP |= FLAGC; memread(pc); return;
case 0x39: nz(rA &= absY()); return;
case 0x3E: rol(aabsX(rX, 1)); return;
case 0x3D: nz(rA &= absX()); return;
case 0x40: fetch8(); memread(rS|0x100); rP = pop8() & 0xcf; pc = pop16(); return;
case 0x41: nz(rA ^= indX()); return;
case 0x45: nz(rA ^= zp()); return;
case 0x46: lsr(fetch8()); return;
case 0x48: memread(pc); push8(rA); return;
case 0x49: nz(rA ^= imm()); return;
case 0x4A:
rP &= ~(FLAGN | FLAGZ | FLAGC);
rP |= rA & 1;
rA >>= 1;
if(rA == 0) rP |= FLAGZ;
if(rA & 0x80) rP |= FLAGN;
memread(pc);
return;
case 0x4C: pc = fetch16(); return;
case 0x4D: nz(rA ^= abso()); return;
case 0x4E: lsr(fetch16()); return;
case 0x51: nz(rA ^= indY()); return;
case 0x56: lsr(azpX(rX)); return;
case 0x58: rP &= ~FLAGI; memread(pc); return;
case 0x50: if((rP & FLAGV) == 0) branch(); else fetch8(); return;
case 0x55: nz(rA ^= zpX()); return;
case 0x59: nz(rA ^= absY()); return;
case 0x5D: nz(rA ^= absX()); return;
case 0x5E: lsr(aabsX(rX, 1)); return;
case 0x60: fetch8(); memread(rS | 0x100); pc = pop16(); fetch8(); return;
case 0x61: adc(indX()); return;
case 0x65: adc(zp()); return;
case 0x66: ror(fetch8()); return;
case 0x68: memread(pc); memread(0x100|rS); nz(rA = pop8()); return;
case 0x69: adc(imm()); return;
case 0x6A:
a = rP & FLAGC;
rP &= ~(FLAGC | FLAGN | FLAGZ);
rP |= rA & 1;
rA = (rA >> 1) | (a << 7);
if(rA & 0x80) rP |= FLAGN;
if(rA == 0) rP |= FLAGZ;
memread(pc);
return;
case 0x6C: v = fetch16(); pc = memread(v) | (memread((v & 0xFF00) | (u8int)(v+1)) << 8); return;
case 0x6D: adc(abso()); return;
case 0x6E: ror(fetch16()); return;
case 0x70: if((rP & FLAGV) != 0) branch(); else fetch8(); return;
case 0x71: adc(indY()); return;
case 0x75: adc(zpX()); return;
case 0x76: ror(azpX(rX)); return;
case 0x78: rP |= FLAGI; memread(pc); return;
case 0x79: adc(absY()); return;
case 0x7D: adc(absX()); return;
case 0x7E: ror(aabsX(rX, 1)); return;
case 0x81: memwrite(aindX(), rA); return;
case 0x84: memwrite(fetch8(), rY); return;
case 0x85: memwrite(fetch8(), rA); return;
case 0x86: memwrite(fetch8(), rX); return;
case 0x88: nz(--rY); memread(pc); return;
case 0x8A: nz(rA = rX); memread(pc); return;
case 0x8C: memwrite(fetch16(), rY); return;
case 0x8D: memwrite(fetch16(), rA); return;
case 0x8E: memwrite(fetch16(), rX); return;
case 0x90: if((rP & FLAGC) == 0) branch(); else fetch8(); return;
case 0x91: memwrite(aindY(1), rA); return;
case 0x94: memwrite(azpX(rX), rY); return;
case 0x95: memwrite(azpX(rX), rA); return;
case 0x96: memwrite(azpX(rY), rX); return;
case 0x98: nz(rA = rY); memread(pc); return;
case 0x99: memwrite(aabsX(rY, 1), rA); return;
case 0x9A: rS = rX; memread(pc); return;
case 0x9D: memwrite(aabsX(rX, 1), rA); return;
case 0xA0: nz(rY = imm()); return;
case 0xA1: nz(rA = indX()); return;
case 0xA2: nz(rX = imm()); return;
case 0xA4: nz(rY = zp()); return;
case 0xA5: nz(rA = zp()); return;
case 0xA6: nz(rX = zp()); return;
case 0xA8: nz(rY = rA); memread(pc); return;
case 0xA9: nz(rA = imm()); return;
case 0xAA: nz(rX = rA); memread(pc); return;
case 0xAC: nz(rY = abso()); return;
case 0xAE: nz(rX = abso()); return;
case 0xAD: nz(rA = abso()); return;
case 0xB0: if((rP & FLAGC) != 0) branch(); else fetch8(); return;
case 0xB1: nz(rA = indY()); return;
case 0xB4: nz(rY = zpX()); return;
case 0xB5: nz(rA = zpX()); return;
case 0xB6: nz(rX = zpY()); return;
case 0xB8: rP &= ~FLAGV; memread(pc); return;
case 0xB9: nz(rA = absY()); return;
case 0xBA: nz(rX = rS); memread(pc); return;
case 0xBC: nz(rY = absX()); return;
case 0xBD: nz(rA = absX()); return;
case 0xBE: nz(rX = absY()); return;
case 0xC1: cmp(rA, indX()); return;
case 0xC5: cmp(rA, zp()); return;
case 0xC9: cmp(rA, imm()); return;
case 0xCD: cmp(rA, abso()); return;
case 0xD0: if((rP & FLAGZ) == 0) branch(); else fetch8(); return;
case 0xD1: cmp(rA, indY()); return;
case 0xD5: cmp(rA, zpX()); return;
case 0xD8: rP &= ~FLAGD; memread(pc); return;
case 0xD9: cmp(rA, absY()); return;
case 0xDD: cmp(rA, absX()); return;
case 0xC0: cmp(rY, imm()); return;
case 0xC4: cmp(rY, zp()); return;
case 0xC6: dec(fetch8()); return;
case 0xC8: nz(++rY); memread(pc); return;
case 0xCA: nz(--rX); memread(pc); return;
case 0xCC: cmp(rY, abso()); return;
case 0xCE: dec(fetch16()); return;
case 0xD6: dec(azpX(rX)); return;
case 0xDE: dec(aabsX(rX, 1)); return;
case 0xE0: cmp(rX, imm()); return;
case 0xE1: sbc(indX()); return;
case 0xE4: cmp(rX, zp()); return;
case 0xE5: sbc(zp()); return;
case 0xE6: inc(fetch8()); return;
case 0xE8: nz(++rX); memread(pc); return;
case 0xE9: sbc(imm()); return;
case 0xEA: memread(pc); return;
case 0xEC: cmp(rX, abso()); return;
case 0xED: sbc(abso()); return;
case 0xEE: inc(fetch16()); return;
case 0xF0: if((rP & FLAGZ) != 0) branch(); else fetch8(); return;
case 0xF1: sbc(indY()); return;
case 0xF5: sbc(zpX()); return;
case 0xF6: inc(azpX(rX)); return;
case 0xF8: rP |= FLAGD; memread(pc); return;
case 0xF9: sbc(absY()); return;
case 0xFD: sbc(absX()); return;
case 0xFE: inc(aabsX(rX, 1)); return;
default:
print("undefined %#x (pc %#x)\n", op, curpc);
return;
}
}

95
sys/src/games/c64/dat.h Normal file
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typedef char s8int;
extern u8int reg[47], crom[4096], krom[8192], brom[8192], cram[1024], cart[16384];
extern u16int pc, curpc;
extern u8int rP;
extern int nrdy, irq, nmi, irqen, nmien, trace;
extern u8int pla;
extern uchar *tape, tapever, tapeplay;
extern ulong tapelen;
extern u16int ppux, ppuy, picw, pich;
extern u64int keys;
extern u16int joys;
extern int scale, region;
enum {
FLAGC = 1<<0,
FLAGZ = 1<<1,
FLAGI = 1<<2,
FLAGD = 1<<3,
FLAGB = 1<<4,
FLAGV = 1<<6,
FLAGN = 1<<7,
};
enum {
IRQRASTER = 1<<0,
IRQBGCOLL = 1<<1,
IRQSPRCOLL = 1<<2,
IRQLIGHT = 1<<3,
IRQTIMERA = 1<<4,
IRQTIMERB = 1<<5,
IRQTOD = 1<<6,
IRQSDR = 1<<7,
IRQFLAG = 1<<8,
IRQRESTORE = 1<<9,
};
enum{
MSBX = 0x10,
CTRL1 = 0x11,
RASTER = 0x12,
SPREN = 0x15,
CTRL2 = 0x16,
SPRYE = 0x17,
MEMP = 0x18,
IRQLATCH = 0x19,
IRQEN = 0x1a,
SPRDP = 0x1b,
SPRMC = 0x1c,
SPRXE = 0x1d,
SPRSPR = 0x1e,
SPRBG = 0x1f,
EC = 0x20,
BG0 = 0x21,
BG1 = 0x22,
BG2 = 0x23,
BG3 = 0x24,
SPRMC0 = 0x25,
SPRMC1 = 0x26,
SPRCOL = 0x27
};
enum {
LORAM = 1,
HIRAM = 2,
CHAREN = 4,
GAME = 8,
EXROM = 16,
ECM = 0x40,
BMM = 0x20,
DEN = 0x10,
RSEL = 0x08,
CSEL = 0x08,
MCM = 0x10,
};
enum {
BILLION = 1000*1000*1000,
MILLION = 1000*1000,
HZ = 3579545,
RATE = 44100,
SAMPDIV = HZ / 3 / RATE,
};
enum {
NTSC,
NTSC0,
PAL
};

11
sys/src/games/c64/fns.h Normal file
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u8int memread(u16int);
void memwrite(u16int, u8int);
void step(void);
void vicstep(void);
void flush(void);
u8int vmemread(u16int);
void io(void);
void memreset(void);
void vicreset(void);
void bordset(void);
void progress(int, int);

304
sys/src/games/c64/mem.c Normal file
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#include <u.h>
#include <libc.h>
#include <thread.h>
#include "dat.h"
#include "fns.h"
u8int pla;
u8int ram[65536], krom[8192], brom[8192], crom[4096], cart[16384], cram[1024];
u8int reg[47];
u16int vicbank;
u8int cia[32];
u16int timer[4], timrel[4];
enum {
TIMEREN = 1,
TIMERUND = 2,
TIMERSTOP = 8,
TIMERASRC = 0x20,
TIMERBSRC = 0x60,
TIMERBSYS = 0,
TIMERBA = 0x40,
};
u8int
ciaread(int n, u8int a)
{
u8int r;
int i;
switch(a){
case 0:
return (cia[0] | ~cia[2]) & (~joys >> 5 | 0xe0);
case 1:
if(!n){
r = 0;
for(i = 0; i < 8; i++)
if((cia[0] & 1<<i) == 0)
r |= keys >> 8 * i;
return (cia[1] | ~cia[3]) & ~r & (~joys | 0xe0);
}
break;
case 4: return timer[n*2];
case 5: return timer[n*2] >> 8;
case 6: return timer[n*2+1];
case 7: return timer[n*2+1] >> 8;
case 13:
if(n){
r = nmi >> 4 & 0x1f | ((nmi & nmien & 0x1f0) != 0) << 7;
nmi &= ~0x1f0;
return r;
}else{
r = irq >> 4 & 0x1f | ((irq & irqen & 0x1f0) != 0) << 7;
irq &= ~0x1f0;
return r;
}
}
return cia[n * 16 + a];
}
void
ciawrite(int n, u8int a, u8int v)
{
switch(a){
case 0:
if(n)
vicbank = (~v & 3) << 14;
break;
case 4: timrel[n*2] = v | timrel[n*2] & 0xff00; break;
case 5: timrel[n*2] = v << 8 | timrel[n*2] & 0xff; break;
case 6: timrel[n*2+1] = v | timrel[n*2+1] & 0xff00; break;
case 7: timrel[n*2+1] = v << 8 | timrel[n*2+1] & 0xff; break;
case 13:
if(n)
if((v & 0x80) != 0)
nmien |= v << 4 & 0x1f0;
else
nmien &= ~(v << 4 & 0x1f0);
else
if((v & 0x80) != 0)
irqen |= v << 4 & 0x1f0;
else
irqen &= ~(v << 4 & 0x1f0);
break;
case 14: case 15:
if((v & 0x10) != 0){
timer[n * 2 + (a & 1)] = timrel[n * 2 + (a & 1)];
v &= ~0x10;
}
break;
}
cia[n * 16 + a] = v;
}
u8int
mioread(u16int a)
{
u8int b, v;
switch(a & 0xc00){
case 0:
b = a & 63;
switch(b){
case CTRL1:
return reg[b] & 0x7f | ppuy >> 1 & 0x80;
case RASTER:
return ppuy;
case IRQLATCH:
return irq & 0xf | (irq & irqen & 0xf) + 0x7f & 0x80;
case IRQEN:
return irqen & 0xf;
case SPRSPR:
case SPRBG:
v = reg[b];
reg[b] = 0;
return v;
}
if(b >= 0x20)
return reg[b] | 0xf0;
if(b >= 47)
return 0xff;
return reg[b];
case 0x800:
return cram[a & 0x3ff];
case 0xc00:
if((a & 0x200) == 0)
return ciaread(a >> 8 & 1, a & 0xf);
default:
return 0xff;
}
}
void
miowrite(u16int a, u8int v)
{
u8int b;
switch(a & 0xc00){
case 0:
b = a & 63;
if(b >= 0x20)
v &= 0xf;
switch(b){
case CTRL2: v |= 0xc0; break;
case IRQLATCH:
v |= 0xf0;
irq &= ~(v & 0xf);
break;
case IRQEN:
irqen = irqen & ~0xf | v & 0xf;
v |= 0xf0;
break;
}
if(b < 47)
reg[b] = v;
if(b == CTRL1 || b == CTRL2)
bordset();
return;
case 0x800:
cram[a & 0x3ff] = v & 0xf;
return;
case 0xc00:
if((a & 0x200) == 0)
ciawrite(a >> 8 & 1, a & 0xf, v);
return;
}
}
void
tapestep(void)
{
static int tapectr;
static int idx;
if((ram[1] & 1<<5) != 0)
return;
if(tapectr == 0){
if(idx >= tapelen){
progress(0, 0);
tapeplay = 0;
idx = 0;
return;
}
tapectr = tape[idx++] << 3;
if(tapever == 1 && tapectr == 0){
tapectr = tape[idx++];
tapectr |= tape[idx++] << 8;
tapectr |= tape[idx++] << 16;
}
progress(idx, tapelen);
}else{
tapectr--;
if(tapectr == 0)
irq |= IRQFLAG;
}
}
void
timerstep(void)
{
int i, at;
u8int a, b;
u16int *t;
for(i = 0; i < 2; i++){
a = cia[i * 16 + 14];
b = cia[i * 16 + 15];
at = 0;
t = &timer[2 * i];
if((a & (TIMEREN|TIMERASRC)) == TIMEREN){
t[0]--;
if(t[0] == 0){
at = 1;
if(i)
nmi |= IRQTIMERA;
else
irq |= IRQTIMERA;
if((a & TIMERSTOP) != 0)
cia[i * 16 + 14] &= ~TIMEREN;
t[0] = timrel[2 * i];
}
}
if((b & TIMEREN) != 0 && ((b & TIMERBSRC) == TIMERBSYS || (b & TIMERBSRC) == TIMERBA && at)){
t[1]--;
if(t[1] == 0){
if(i)
nmi |= IRQTIMERB;
else
irq |= IRQTIMERB;
if((b & TIMERSTOP) == 0)
cia[i * 16 + 15] &= ~TIMEREN;
t[1] = timrel[2 * i + 1];
}
}
}
if(tapeplay)
tapestep();
}
void
io(void)
{
vicstep();
timerstep();
}
u8int
memread(u16int a)
{
io();
if(a == 1)
return ram[1] & ~(1<<4) | (tapeplay ^ 1) << 4;
switch(a >> 12){
case 8: case 9:
if((pla & (EXROM|GAME)) == EXROM || (pla & (EXROM|HIRAM|LORAM)) == (HIRAM|LORAM))
return cart[a & 0x1fff];
goto def;
case 10: case 11:
if((pla & (GAME|HIRAM|LORAM)) == (GAME|HIRAM|LORAM))
return brom[a & 0x1fff];
if((pla & (EXROM|GAME|HIRAM)) == HIRAM)
return cart[8192 + (a & 0x1fff)];
goto def;
case 13:
if((pla & (HIRAM|LORAM)) == 0 || pla == 1)
goto def;
if((pla & CHAREN) == 0 && (pla & (EXROM|GAME)) != EXROM)
return crom[a & 0xfff];
return mioread(a & 0xfff);
case 14: case 15:
if((pla & (EXROM|GAME)) == EXROM)
return cart[8192 + (a & 0x1fff)];
if((pla & HIRAM) == HIRAM)
return krom[a & 0x1fff];
def:
default:
return ram[a];
}
}
void
memwrite(u16int a, u8int v)
{
if(a >> 12 == 13 && !((pla & (HIRAM|LORAM)) == 0 || pla == 1 || (pla & CHAREN) == 0 && (pla & (EXROM|GAME)) != EXROM))
miowrite(a & 0xfff, v);
ram[a] = v;
if(a == 1)
pla = pla & ~7 | v & 7;
io();
}
u8int
vmemread(u16int a)
{
a |= vicbank;
if((a & 0x7000) == 0x1000)
return crom[a & 0xfff];
return ram[a];
}
void
memreset(void)
{
pla = 0x1f;
}

13
sys/src/games/c64/mkfile Normal file
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@ -0,0 +1,13 @@
</$objtype/mkfile
BIN=/$objtype/bin/games
TARG=2600
OFILES=\
c64.$O\
cpu.$O\
mem.$O\
vic.$O\
HFILES=dat.h fns.h
</sys/src/cmd/mkone

366
sys/src/games/c64/vic.c Normal file
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@ -0,0 +1,366 @@
#include <u.h>
#include <libc.h>
#include <thread.h>
#include "dat.h"
#include "fns.h"
int region, picidx;
u16int ppux, ppuy, lastx, wrapx, maxy, lvis, rvis, uvis, dvis, picw, pich, lbord, rbord, ubord, dbord, spr0;
u16int vc, vcbase, vmli;
u8int badln, rc, displ, fract, visreg, hbord, vbord, rbord0, lbord0;
u16int chrp[40];
u8int pic[400*300*3*3];
u64int pxs, npxs, npxs0, opxs;
u8int fg;
typedef struct spr spr;
enum {
SPRFDMA = 1,
SPRFYEX = 2,
SPRFDISP = 4,
};
struct spr {
u8int flags;
u32int data;
u8int mc, mcbase, dp;
u16int x;
} sp[8];
void
bordset(void)
{
int r, c;
r = (reg[CTRL1] & RSEL) != 0;
c = (reg[CTRL2] & CSEL) != 0;
lbord = c ? 0x14 : 0x1c;
lbord0 = c ? 0xf0 : 0xe0;
rbord = c ? 0x154 : 0x14c;
rbord0 = c ? 0x0f : 0x3f;
ubord = r ? 0x33 : 0x37;
dbord = r ? 0xfb : 0xf7;
if((reg[CTRL1] & DEN) == 0)
ubord = -1;
}
void
vicreset(void)
{
switch(region){
case NTSC0:
lastx = 0x1fc;
wrapx = 0x19c;
maxy = 262;
picw = 412;
pich = 234;
spr0 = 0x16c;
lvis = 0x1e4;
rvis = 0x184;
uvis = 41;
dvis = 13;
break;
case NTSC:
lastx = 0x1fc;
wrapx = 0x19c;
maxy = 263;
picw = 419;
pich = 235;
spr0 = 0x174;
lvis = 0x1e4;
rvis = 0x18c;
uvis = 41;
dvis = 13;
break;
case PAL:
lastx = 0x1f4;
wrapx = 0x194;
maxy = 312;
picw = 404;
pich = 284;
spr0 = 0x164;
lvis = 0x1dc;
rvis = 0x17c;
uvis = 16;
dvis = 300;
break;
}
ppux = 4;
ppuy = 0;
bordset();
}
void
pixeldraw(u64int p, int n)
{
int i;
static u8int cr[] = {0, 255, 136, 170, 204, 0, 0, 238, 221, 102, 255, 51, 119, 170, 0, 187};
static u8int cg[] = {0, 255, 0, 255, 68, 204, 0, 238, 136, 68, 119, 51, 119, 255, 136, 187};
static u8int cb[] = {0, 255, 0, 238, 204, 85, 170, 119, 85, 0, 119, 51, 119, 102, 255, 187};
u8int *q, c;
q = pic + picidx * 4;
for(i = 0; i < n; i++){
c = p >> 56;
p <<= 8;
q[4 * i] = cb[c];
q[4 * i + 1] = cg[c];
q[4 * i + 2] = cr[c];
}
picidx += n;
}
void
pixels(u8int d, u16int c)
{
u8int c0, c1, c2, n;
int i;
npxs0 = npxs;
npxs = 0;
switch((reg[CTRL1] & (ECM|BMM) | reg[CTRL2] & MCM) >> 4){
case 0:
c0 = c >> 8;
normal:
fg = d;
for(i = 0; i < 8; i++){
npxs = npxs << 8 | ((d & 0x80) != 0 ? c0 : reg[BG0]);
d <<= 1;
}
break;
case 1:
c0 = c >> 8 & 7;
if((c & 0x800) == 0)
goto normal;
fg = d & 0xaa | d >> 1 & 0x55;
for(i = 0; i < 8; i += 2){
n = d >> 6;
npxs = npxs << 16 | (n == 3 ? c0 : reg[BG0 + n]) * 0x101;
d <<= 2;
}
break;
case 2:
c0 = c & 15;
c1 = c >> 4 & 15;
fg = d;
for(i = 0; i < 8; i++){
npxs = npxs << 8 | ((d & 0x80) != 0 ? c1 : c0);
d <<= 1;
}
break;
case 3:
c0 = c & 15;
c1 = c >> 4 & 15;
c2 = c >> 8;
fg = d & 0xaa | d >> 1 & 0x55;
for(i = 0; i < 8; i += 2){
n = d >> 6;
switch(n){
default: n = reg[BG0]; break;
case 1: n = c1; break;
case 2: n = c0; break;
case 3: n = c2;
}
npxs = npxs << 16 | n * 0x101;
d <<= 2;
}
break;
case 4:
c0 = c >> 8;
fg = d;
for(i = 0; i < 8; i++){
npxs = npxs << 8 | ((d & 0x80) != 0 ? c0 : reg[BG0 + (d >> 6 & 3)]);
d <<= 1;
}
break;
default:
fg = 0;
break;
}
}
void
bgpixels(void)
{
int i, j, x;
u8int h;
u8int spract, s, o;
h = hbord;
opxs = 0;
for(i = 0; i < 8; i++){
if((reg[CTRL2] + 4 & 7) == i)
pxs = i >= 4 ? npxs : npxs0;
o = pxs >> 56;
pxs <<= 8;
x = ppux + i;
spract = 0;
for(j = 0; j < 8; j++)
if((sp[j].flags & SPRFDISP) != 0 && (u16int)(x-sp[j].x) < 48 && (sp[j].data & ((reg[SPRMC]&1<<j)?3:2)<<22) != 0)
spract |= 1<<j;
if((spract & spract - 1) != 0 && vbord == 0){
reg[SPRSPR] |= spract;
irq |= IRQSPRCOLL;
}
if(fg != 0 && spract != 0 && vbord == 0){
reg[SPRBG] |= spract;
irq |= IRQBGCOLL;
}
s = spract & ~(reg[SPRDP] & ((s8int)fg) >> 7);
if(s != 0)
for(j = 0; j < 8; j++)
if((s & 1<<j) != 0){
if((reg[SPRMC] & 1<<j) != 0)
switch(sp[j].data >> 22 & 3){
case 1: o = reg[SPRMC0]; break;
case 2: o = reg[SPRCOL+j]; break;
case 3: o = reg[SPRMC1]; break;
}
else
o = reg[SPRCOL+j];
break;
}
if((h & 0x80) != 0)
o = reg[EC];
opxs = opxs << 8 | o;
h <<= 1;
fg <<= 1;
for(j = 0; j < 8; j++)
if((u16int)(x-sp[j].x) < 48 && ((reg[SPRXE] & 1<<j) == 0 || (x-sp[j].x & 1) != 0))
if((reg[SPRMC] & 1<<j) != 0){
if((x-sp[j].x & 1) != 0)
sp[j].data <<= 2;
}else
sp[j].data <<= 1;
}
}
void
vicstep(void)
{
u16int gaddr;
int i;
if(ppuy == 0x30 && (reg[CTRL1] & DEN) != 0)
fract = 1;
badln = ((ppuy ^ reg[CTRL1]) & 7) == 0 && fract;
hbord = ((s8int)(hbord << 7)) >> 7;
if(ppux == rbord && hbord == 0)
hbord = rbord0;
else if(ppux == lbord){
if(ppuy == dbord)
vbord = 1;
if(ppuy == ubord)
vbord = 0;
if(!vbord)
hbord = lbord0;
}
if(badln)
displ = 1;
if(ppux == 4){
vc = vcbase;
vmli = 0;
if(badln)
rc = 0;
}
if(ppux == 12)
for(i = 0; i < 8; i++){
if((sp[i].flags & SPRFDISP) == 0 || (reg[SPRYE] & 1<<i) != 0 && (sp[i].flags & SPRFYEX) == 0)
continue;
sp[i].mcbase += 3;
if(sp[i].mcbase == 63)
sp[i].flags &= ~(SPRFDMA|SPRFDISP);
}
if(ppux >= 0x14 && ppux <= 0x14c){
if((reg[CTRL1] & BMM) != 0)
gaddr = (reg[MEMP] & 0x08) << 10 | vc << 3 | rc;
else
gaddr = (reg[MEMP] & 0x0e) << 10 | (chrp[vmli] & 0xff) << 3 | rc;
if(!displ)
gaddr = 0x3fff;
if((reg[CTRL1] & ECM) != 0)
gaddr &= ~0x600;
pixels(vmemread(gaddr) & -displ, chrp[vmli] & -displ);
vmli++;
vc = vc + 1 & 0x3ff;
}
if(visreg && (ppux >= lvis || ppux < rvis)){
bgpixels();
pixeldraw(opxs, ppux == lvis ? region == NTSC ? 3 : 4 : 8);
}
if(ppux == 0x14c){
for(i = 0; i < 8; i++){
if((reg[SPRYE] & 1<<i) != 0)
sp[i].flags ^= SPRFYEX;
if((reg[SPREN] & 1<<i) == 0 || reg[2*i+1] != (u8int)ppuy)
continue;
sp[i].flags |= SPRFDMA;
sp[i].mcbase = 0;
if((reg[SPRYE] & 1<<i) != 0)
sp[i].flags &= ~SPRFYEX;
}
}else if(ppux == 0x154)
npxs = reg[BG0] * 0x0101010101010101ULL;
if(badln){
if(ppux == lastx - 8)
nrdy = 1;
else if(ppux >= 0xc && ppux <= 0x144)
chrp[vmli] = vmemread(vc | (reg[MEMP] & 0xf0) << 6) | cram[vc] << 8;
else if(ppux == 0x154)
nrdy = 0;
}
if(ppux == 0x164){
if(displ && rc == 7){
displ = badln;
vcbase = vc;
}
if(displ)
rc = rc + 1 & 7;
for(i = 0; i < 8; i++){
sp[i].mc = sp[i].mcbase;
if((sp[i].flags & SPRFDMA) != 0 && reg[2*i+1] == (u8int)ppuy)
sp[i].flags |= SPRFDISP;
}
}
if((u16int)(ppux - spr0) < 128){
i = ppux - spr0 >> 4;
nrdy = (sp[i].flags & SPRFDMA) != 0;
if((ppux & 8) == 0){
sp[i].dp = vmemread((reg[MEMP] & 0xf0) << 6 | 0x3f8 | i);
sp[i].x = nrdy ? reg[2 * i] | reg[MSBX] << 8 - i & 0x100 : -1;
if(nrdy)
sp[i].data = vmemread(sp[i].dp << 6 | sp[i].mc++) << 16;
}else if(nrdy){
sp[i].data = sp[i].data & 0xff00ff | vmemread(sp[i].dp << 6 | sp[i].mc++) << 8;
sp[i].data = sp[i].data & 0xffff00 | vmemread(sp[i].dp << 6 | sp[i].mc++);
}
}else if(ppux - spr0 == 128)
nrdy = 0;
if(ppux == wrapx){
ppuy++;
if(ppuy == maxy){
flush();
ppuy = 0;
vcbase = 0;
}
if((ppuy & 0xff) == reg[RASTER] && ((ppuy ^ reg[CTRL1] << 1) & 0x100) == 0)
irq |= IRQRASTER;
if(ppuy == dbord)
vbord = 1;
else if(ppuy == ubord)
vbord = 0;
else if(ppuy == dvis)
visreg = 0;
if(ppuy == uvis){
picidx = 0;
visreg = 1;
}
if(ppuy == 0xf7)
fract = 0;
}
if(ppux == lastx)
ppux = 4;
else
ppux += 8;
}