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// deno-lint-ignore-file no-case-declarations
import type The65c02 from "../65c02.ts";
export default function (this: The65c02, mode: string) {
switch (mode) {
case 'zero-page':
// set PC to where the ZP address is
this.programCounter.increment()
const zpa = this.readPC()
this.io.address.set(zpa.num());
this.read();
let v = this.io.data.num();
v++
v &= 0xFF
this.io.data.set(v)
this.write()
this.flagZN(v)
this.programCounter.increment()
break;
case 'zero-page, X-indexed':
// set PC to where the ZP address is
this.programCounter.increment()
const zpax = this.readPC()
this.io.address.set(zpax.num() + this.regX.num());
this.read();
let vzx = this.io.data.num();
vzx++
vzx &= 0xFF
this.io.data.set(vzx)
this.write()
this.flagZN(vzx)
this.programCounter.increment()
break;
case 'absolute':
// skip over the opcode
this.programCounter.increment()
const lo_abit = this.readPC().num()
this.programCounter.increment()
const hi_abit = this.readPC().num()
this.io.address.set((hi_abit << 8) | lo_abit)
this.read()
let va = this.io.data.num();
va++
va &= 0xFF
this.io.data.set(va)
this.write()
this.programCounter.increment()
break;
case 'absolute, X-indexed':
// skip over the opcode
this.programCounter.increment()
const lo_axbit = this.readPC().num()
this.programCounter.increment()
const hi_axbit = this.readPC().num()
this.io.address.set(((hi_axbit << 8) | lo_axbit) + this.regX.num())
this.read()
let vax = this.io.data.num();
vax++
vax &= 0xFF
this.io.data.set(vax)
this.write()
this.programCounter.increment()
break;
default:
throw 'wha';
}
}
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