8bitworkshop/src/machine/vicdual.ts

176 lines
5.0 KiB
TypeScript

import { Z80, Z80State } from "../common/cpu/ZilogZ80";
import { BasicScanlineMachine } from "../common/devices";
import { KeyFlags, newAddressDecoder, padBytes, Keys, makeKeycodeMap, newKeyboardHandler } from "../common/emu";
import { TssChannelAdapter, MasterAudio, AY38910_Audio } from "../common/audio";
const CARNIVAL_KEYCODE_MAP = makeKeycodeMap([
[Keys.A, 2, -0x20],
[Keys.B, 2, -0x40],
[Keys.LEFT, 1, -0x10],
[Keys.RIGHT, 1, -0x20],
[Keys.UP, 1, -0x40],
[Keys.DOWN, 1, -0x80],
[Keys.START, 2, -0x10],
[Keys.P2_START, 3, -0x20],
[Keys.SELECT, 3, 0x8],
]);
const XTAL = 15468000.0;
const scanlinesPerFrame = 0x106;
const vblankStart = 0xe0;
const vsyncStart = 0xec;
const vsyncEnd = 0xf0;
const cpuFrequency = XTAL / 8;
const hsyncFrequency = XTAL / 3 / scanlinesPerFrame;
const vsyncFrequency = hsyncFrequency / 0x148;
const cpuCyclesPerLine = cpuFrequency / hsyncFrequency;
const timerFrequency = 500; // input 2 bit 0x8
const cyclesPerTimerTick = cpuFrequency / (2 * timerFrequency);
const audioOversample = 2;
const audioSampleRate = 60 * scanlinesPerFrame; // why not hsync?
export class VicDual extends BasicScanlineMachine {
cpuFrequency = XTAL / 8; // MHz
canvasWidth = 256;
numTotalScanlines = 262;
numVisibleScanlines = 224;
defaultROMSize = 0x4040;
sampleRate = audioSampleRate * audioOversample;
cpuCyclesPerLine = cpuCyclesPerLine|0;
rotate = -90;
cpu: Z80 = new Z80();
ram = new Uint8Array(0x1000);
psg: AY38910_Audio;
display: VicDualDisplay;
audioadapter;
constructor() {
super();
this.connectCPUMemoryBus(this);
this.connectCPUIOBus(this.newIOBus());
this.inputs.set([0xff, 0xff, 0xff, 0xff ^ 0x8]); // most things active low
this.display = new VicDualDisplay();
this.handler = newKeyboardHandler(this.inputs, CARNIVAL_KEYCODE_MAP, this.getKeyboardFunction());
this.psg = new AY38910_Audio(new MasterAudio());
this.audioadapter = new TssChannelAdapter(this.psg.psg, audioOversample, this.sampleRate);
}
getKeyboardFunction() {
return (o) => {
// reset when coin inserted
if (o.index == 3 && o.mask == 0x8) {
this.cpu.reset();
console.log("coin inserted");
console.log(this.inputs)
}
}
};
read = newAddressDecoder([
[0x0000, 0x7fff, 0x3fff, (a) => { return this.rom ? this.rom[a] : null; }],
[0x8000, 0xffff, 0x0fff, (a) => { return this.ram[a]; }],
]);
write = newAddressDecoder([
[0x8000, 0xffff, 0x0fff, (a, v) => { this.ram[a] = v; }],
]);
newIOBus() {
return {
read: (addr) => {
return this.inputs[addr & 3];
},
write: (addr, val) => {
if (addr & 0x1) { this.psg.selectRegister(val & 0xf); }; // audio 1
if (addr & 0x2) { this.psg.setData(val); }; // audio 2
if (addr & 0x8) { }; // TODO: assert coin status
if (addr & 0x40) { this.display.palbank = val & 3; }; // palette
}
};
}
reset() {
super.reset();
this.psg.reset();
}
startScanline() {
this.inputs[2] &= ~0x8;
this.inputs[2] |= ((this.frameCycles / cyclesPerTimerTick) & 1) << 3;
if (this.scanline == vblankStart) this.inputs[1] |= 0x8;
if (this.scanline == vsyncEnd) this.inputs[1] &= ~0x8;
this.audio && this.audioadapter.generate(this.audio);
}
drawScanline() {
this.display.drawScanline(this.ram, this.pixels, this.scanline);
}
loadROM(data) {
super.loadROM(data);
if (data.length >= 0x4020 && (data[0x4000] || data[0x401f])) {
this.display.colorprom = data.slice(0x4000, 0x4020);
}
}
loadState(state) {
super.loadState(state);
this.display.palbank = state.pb;
}
saveState() {
var state = super.saveState();
state['pb'] = this.display.palbank;
return state;
}
}
class VicDualDisplay {
palbank: number = 0;
palette = [
0xff000000, // black
0xff0000ff, // red
0xff00ff00, // green
0xff00ffff, // yellow
0xffff0000, // blue
0xffff00ff, // magenta
0xffffff00, // cyan
0xffffffff // white
];
// default PROM
colorprom = [
0xe0, 0x60, 0x20, 0x60, 0xc0, 0x60, 0x40, 0xc0,
0x20, 0x40, 0x60, 0x80, 0xa0, 0xc0, 0xe0, 0x0e,
0xe0, 0xe0, 0xe0, 0xe0, 0x60, 0x60, 0x60, 0x60,
0xe0, 0xe0, 0xe0, 0xe0, 0xe0, 0xe0, 0xe0, 0xe0,
];
// videoram 0xc000-0xc3ff
// RAM 0xc400-0xc7ff
// charram 0xc800-0xcfff
drawScanline(ram, pixels: Uint32Array, sl: number) {
if (sl >= 224) return;
var pixofs = sl * 256;
var outi = pixofs; // starting output pixel in frame buffer
var vramofs = (sl >> 3) << 5; // offset in VRAM
var yy = sl & 7; // y offset within tile
for (var xx = 0; xx < 32; xx++) {
var code = ram[vramofs + xx];
var data = ram[0x800 + (code << 3) + yy];
var col = (code >> 5) + (this.palbank << 3);
var color1 = this.palette[(this.colorprom[col] >> 1) & 7];
var color2 = this.palette[(this.colorprom[col] >> 5) & 7];
for (var i = 0; i < 8; i++) {
var bm = 128 >> i;
pixels[outi] = (data & bm) ? color2 : color1;
outi++;
}
}
}
}