nes-emu/apu/registers/TriangleLCLTimerHigh.js

A NES emulator

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var _registers = require("../../registers");
var _constants = require("../constants");
/** Sets the high 3 bits of the Triangle channel's timer and its length counter. */
class TriangleLCLTimerHigh extends _registers.WriteOnlyInMemoryRegister {
  constructor() {
    super();
    this.addReadOnlyField("timerHigh", 0, 3).addReadOnlyField("lengthCounterLoad", 3, 5);
  }

  /** Updates the length counter and schedules a linear length counter update (next quarter beat). */
  writeAt(__, byte) {
    this.setValue(byte);
    const triangle = this.context.apu.channels.triangle;
    triangle.lengthCounter.counter = _constants.lengthTable[this.lengthCounterLoad];
    triangle.linearLengthCounter.reloadFlag = true;
  }
}
exports.default = TriangleLCLTimerHigh;