broken-neees/apu/APU.js

A really broken NEEES emulator that introduces glitches and random bugs on purpose!

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.default = void 0;
var _AudioRegisters = _interopRequireDefault(require("./AudioRegisters"));
var _FrameSequencer = _interopRequireDefault(require("./FrameSequencer"));
var _PulseChannel = _interopRequireDefault(require("./PulseChannel"));
var _TriangleChannel = _interopRequireDefault(require("./TriangleChannel"));
var _NoiseChannel = _interopRequireDefault(require("./NoiseChannel"));
var _DMCChannel = _interopRequireDefault(require("./DMCChannel"));
function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
function _typeof(obj) { "@babel/helpers - typeof"; return _typeof = "function" == typeof Symbol && "symbol" == typeof Symbol.iterator ? function (obj) { return typeof obj; } : function (obj) { return obj && "function" == typeof Symbol && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }, _typeof(obj); }
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, _toPropertyKey(descriptor.key), descriptor); } }
function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); Object.defineProperty(Constructor, "prototype", { writable: false }); return Constructor; }
function _toPropertyKey(arg) { var key = _toPrimitive(arg, "string"); return _typeof(key) === "symbol" ? key : String(key); }
function _toPrimitive(input, hint) { if (_typeof(input) !== "object" || input === null) return input; var prim = input[Symbol.toPrimitive]; if (prim !== undefined) { var res = prim.call(input, hint || "default"); if (_typeof(res) !== "object") return res; throw new TypeError("@@toPrimitive must return a primitive value."); } return (hint === "string" ? String : Number)(input); }
var FREQ_APU_HZ = 894887;
var APU_SAMPLE_RATE = 44100;
var STEPS_PER_SAMPLE = Math.floor(FREQ_APU_HZ / APU_SAMPLE_RATE);
var APU = /*#__PURE__*/function () {
  function APU(cpu) {
    _classCallCheck(this, APU);
    this.cpu = cpu;
    this.sampleCounter = 0;
    this.sample = 0;
    this.registers = new _AudioRegisters.default(this);
    this.frameSequencer = new _FrameSequencer.default(this);
    this.channels = {
      pulses: [new _PulseChannel.default(this, 0, "enablePulse1"), new _PulseChannel.default(this, 1, "enablePulse2")],
      triangle: new _TriangleChannel.default(this),
      noise: new _NoiseChannel.default(this),
      dmc: new _DMCChannel.default(this, this.cpu)
    };
  }
  _createClass(APU, [{
    key: "step",
    value: function step(onSample) {
      this.channels.pulses[0].step();
      this.channels.pulses[1].step();
      this.channels.noise.step();
      this.channels.dmc.step();
      this.sampleCounter++;
      this.frameSequencer.step();
      if (this.sampleCounter === STEPS_PER_SAMPLE) {
        this.sampleCounter = 0;
        var pulse1 = this.channels.pulses[0].sample();
        var pulse2 = this.channels.pulses[1].sample();
        var triangle = this.channels.triangle.sample();
        var noise = this.channels.noise.sample();
        var dmc = this.channels.dmc.sample();
        var pulseOut = 0.00752 * (pulse1 + pulse2);
        var tndOut = 0.00851 * triangle + 0.00494 * noise + 0.00335 * dmc;
        this.sample = pulseOut + tndOut;
        onSample(this.sample, pulse1, pulse2, triangle, noise, dmc);
      }
    }
  }, {
    key: "onQuarterFrameClock",
    value: function onQuarterFrameClock() {
      this.channels.pulses[0].quarterFrame();
      this.channels.pulses[1].quarterFrame();
      this.channels.triangle.quarterFrame();
      this.channels.noise.quarterFrame();
    }
  }, {
    key: "onHalfFrameClock",
    value: function onHalfFrameClock() {
      this.channels.pulses[0].halfFrame();
      this.channels.pulses[1].halfFrame();
      this.channels.triangle.halfFrame();
      this.channels.noise.halfFrame();
    }
  }]);
  return APU;
}();
exports.default = APU;