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// deno-lint-ignore-file no-process-globals
import The65c02 from "./65c02.ts";
import matrix from "./opcode_matrix.json" with { type: "json" };
import { type Buffer } from "node:buffer";
// eater.ts
// a runtime meant to mimic ben eater's 65c02 computer
if (!process.stdin.isRaw)
process.stdin.setRawMode(true)
// the thing used for ram
const ram = new Uint8Array(2**16);
// initiate the emulator
const cpu = new The65c02(function (this: The65c02) {
// since this is controlled by the user it's easy
// to map things into address space
this.io.data.set(ram[this.io.address.num()] ?? 0)
if (this.io.address.num() == 0x5000
&& ram[0x5001])
ram[0x5001] = 0;
}, function (this: The65c02) {
if (this.io.address.num() == 0x5000) {
return Deno.stdout.write(new Uint8Array([this.io.data.num()]))
}
// write
ram[this.io.address.num()] = this.io.data.num()
})
const binStart = 0;
await cpu.loadInstructions()
cpu.stackPointer.set(0xff)
const code = Deno.readFileSync('a.out')
// mem address $0000
ram[0xFFFC] = binStart & 0x00FF
ram[0xFFFD] = (binStart & 0xFF00) >> 8
// write code to ram before execution
for (let offset = 0; offset < code.length; offset++) {
const byte = code[offset];
ram[binStart + offset] = byte;
}
// pull RESB low to reset the 65c02
cpu.io.reset.LO()
cpu.cycle()
//the cpu reset, pull RESB high and start execution!
cpu.io.reset.HI()
let running = true;
process.stdin.on('data', (data: Buffer) => {
if (data[0] == 3)
return running = false;
ram[0x5000] = data[0];
ram[0x5001] = 0x08;
})
// repeat until the cpu requests an interrupt
const clock = setInterval(() => {
if (!running) {
Deno.writeFileSync('ram.bin', ram)
clearInterval(clock)
process.stdin.setRawMode(false);
Deno.exit(0)
}
if(cpu.io.interruptRequest.high && !cpu.IRQBDisable)
cpu.io.interruptRequest.LO();
const instId = ram[cpu.programCounter.num()]
.toString(16)
.padStart(2, '0');
const goog = (matrix as Record<string, { mnemonic: string, mode: string }>)[instId];
if (!goog) {
console.log('uh', instId, 'unknown')
throw 'oh no';
}
const instr = goog;
console.log(`\
PC AC XR YR SP NV-BDIZC
6502: ${cpu.programCounter.num().toString(16).padStart(4, '0')} ${cpu.regA.num().toString(16).padStart(2, '0')} ${cpu.regX.num().toString(16).padStart(2, '0')} ${cpu.regY.num().toString(16).padStart(2, '0')} ${cpu.stackPointer.num().toString(16).padStart(2, '0')} ${cpu.stackPointer.num().toString(2).padStart(8, '0')}`)
console.debug(cpu.programCounter.num().toString(16).padStart(4, '0'),instr.mnemonic, instr.mode)
cpu.cycle();
// 1MHz i think
}, 100)
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