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7800: implemented missing gfx modes, color kill, kangaroo mode

This commit is contained in:
Steven Hugg 2023-07-12 16:21:22 -05:00
parent 02834db8a1
commit d4b8473b86
1 changed files with 68 additions and 18 deletions
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86
src/machine/atari7800.ts
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@ -7,6 +7,7 @@ import { hex, rgb2bgr } from "../common/util";
// https://atarihq.com/danb/a7800.shtml
// https://atarihq.com/danb/files/maria_r1.txt
// https://atarihq.com/danb/files/7800vid.txt
// https://sites.google.com/site/atari7800wiki/
interface Atari7800StateBase {
@ -202,7 +203,8 @@ class MARIA {
doDMA(bus : Bus) {
this.bus = bus;
this.cycles = 0;
this.pixels.fill(this.regs[0x0]);
const pix = this.pixels;
pix.fill(this.regs[0x0]); // background color
if (this.isDMAEnabled()) {
// last line in zone gets additional 8 cycles
this.cycles += this.offset == 0 ? colorClocksShutdownLast : colorClocksShutdownOther;
@ -223,12 +225,12 @@ class MARIA {
let b2 = bus.read(dlhi + ((dlofs+2) & 0x1ff));
let b3 = bus.read(dlhi + ((dlofs+3) & 0x1ff));
let indirect = false;
const writemode = b1 & 0x80;
// extended header?
if ((b1 & 31) == 0) {
var pal = b3 >> 5;
var width = 32 - (b3 & 31);
var xpos = bus.read(dlhi + ((dlofs+4) & 0x1ff));
var writemode = b1 & 0x80;
indirect = (b1 & 0x20) != 0;
dlofs += 5;
this.cycles += 10;
@ -237,17 +239,19 @@ class MARIA {
var xpos = b3;
var pal = b1 >> 5;
var width = 32 - (b1 & 31);
var writemode = 0;
dlofs += 4;
this.cycles += 8;
}
this.indirect = indirect;
let gfxadr = b0 + (((b2 + (indirect?0:this.offset)) & 0xff) << 8);
const gfxadr = b0 + (((b2 + (indirect?0:this.offset)) & 0xff) << 8);
xpos *= 2;
// copy graphics data (direct)
let readmode = (this.regs[0x1c] & 0x3) + (writemode?4:0);
const ctrlreg = this.regs[0x1c];
// gfx mode (readmode + writemode * 4)
const grmode = (ctrlreg & 0x3) + (writemode ? 4 : 0);
// kangaroo mode
const kangaroo = (ctrlreg & 0x4) != 0;
// double bytes?
let dbl = indirect && (this.regs[0x1c] & 0x10) != 0;
const dbl = indirect && (ctrlreg & 0x10) != 0;
if (dbl) { width *= 2; }
//if (this.offset == 0) console.log(hex(dla,4), hex(gfxadr,4), xpos, width, pal, readmode);
for (var i=0; i<width; i++) {
@ -261,23 +265,66 @@ class MARIA {
data = this.readDMA(indadr);
}
// TODO: more modes (https://github.com/gstanton/ProSystem1_3/blob/master/Core/Maria.cpp)
switch (readmode) {
case 0: // 160 A/B
switch (grmode) {
case 0: // 160A
for (let j=0; j<4; j++) {
var col = (data >> 6) & 3;
if (col > 0) {
this.pixels[xpos] = this.pixels[xpos+1] = this.regs[(pal<<2) + col];
let col = (data >> 6) & 3;
if (col || kangaroo) {
pix[xpos] = pix[xpos+1] = this.regs[(pal<<2) + col];
}
data <<= 2;
xpos = (xpos + 2) & 0x1ff;
}
break;
case 2: // 320 B/D (TODO?)
case 3: // 320 A/C
case 3: // 320A
for (let j=0; j<8; j++) {
var col = (data & 128) ? 1 : 0;
if (col > 0) {
this.pixels[xpos] = this.regs[(pal<<2) + col];
let col = (data & 0x80) >> 6;
if (col || kangaroo) {
pix[xpos] = this.regs[(pal<<2) + col];
}
data <<= 1;
xpos = (xpos + 1) & 0x1ff;
}
break;
case 4: // 160B
for (let j=0; j<2; j++) {
let col = ((data >> 6) & 0b0011) + (data & 0b1100);
if ((col & 3) || kangaroo) {
pix[xpos] = pix[xpos+1] = pix[xpos+2] = pix[xpos+3] = this.regs[((pal&4)<<2) + col];
}
data <<= 2;
xpos = (xpos + 2) & 0x1ff;
}
break;
case 6: // 320B
for (let j=0; j<4; j++) {
let col = ((data & 0x80) >> 6) | ((data & 0x08) >> 3);
if (col || kangaroo) {
pix[xpos] = this.regs[(pal<<2) + col];
}
data <<= 1;
xpos = (xpos + 1) & 0x1ff;
}
break;
case 2: // 320D
for (let j=0; j<8; j++) {
let col = ((data & 0x80) >> 6);
col += (j & 1) ? (pal & 1) : ((pal >> 1) & 1);
if (col || kangaroo) {
pix[xpos] = this.regs[(pal<<2) + col];
}
data <<= 1;
xpos = (xpos + 1) & 0x1ff;
}
break;
case 7: // 320C
let data0 = data;
for (let j=0; j<4; j++) {
if (j == 2) data0 <<= 2;
let col = (data & 0x80) >> 6;
let ppal = (pal & 4) | ((data0 >> 2) & 3);
if (col || kangaroo) {
pix[xpos] = this.regs[(ppal<<2) + col];
}
data <<= 1;
xpos = (xpos + 1) & 0x1ff;
@ -491,8 +538,11 @@ export class Atari7800 extends BasicMachine implements RasterFrameBased {
mc += dmaClocks;
// copy line to frame buffer
if (idata) {
const ctrlreg = this.maria.regs[0x1c];
const colorkill = (ctrlreg & 0x80) != 0;
const mask = colorkill ? 0x0f : 0xff;
for (var i=0; i<320; i++) {
idata[iofs++] = COLORS_RGBA[this.maria.pixels[i]];
idata[iofs++] = COLORS_RGBA[this.maria.pixels[i] & mask];
}
}
}