NSF Driver - Assembles an NES ROM from music data

nsfDriver.js

const nsfFormat = [0x4e, 0x45, 0x53, 0x4d, 0x1a]
const version = 1
let totalSongs = 1
let startingSong = 1
const loadAdr = [0x00, 0x80]
const initAdr = [0x00, 0x80]
const playAdr = [0x09, 0x80]

function pad32(string) {
  let name = []
  for (let i = 0; i < 32; i++) {
    if (i < string.length) {
        name.push(string.charCodeAt(i))
    } else {
      name.push(0)
    }
  }
  return name
}

let songName = pad32("Untitled")
let artist = pad32("Unknown")
let copyright = pad32("")

let ntscSpeed = [0xff, 0x40]
let banking = [0,0,0,0,0,0,0,0]
let palSpeed = [0x1d, 0x4e]
let playMode = 3
let expansionAudio = 0
let prgLength = 0

let header = nsfFormat
header.push(version, totalSongs, startingSong);
header = header.concat(loadAdr, initAdr, playAdr,
  songName, artist, copyright, ntscSpeed, banking,
  palSpeed, playMode, expansionAudio, prgLength)

const load = [0x20, 0x0B, 0x80, 0x20, 0x39, 0x80, 0x60, 0x20, 0x88, 0x80, 0x60];
const init = [0xA9, 0x0F, 0x8D, 0x15, 0x40, 0xA9, 0x00, 0x8D, 0x00, 0x02,
    0xA9, 0xFF, 0x8D, 0x03, 0x02, 0x8D, 0x04, 0x02];
const silence = [0xA9, 0x30, 0x8D, 0x05, 0x02, 0x8D, 0x09, 0x02,
    0x8D, 0x11, 0x02, 0xA9, 0x80, 0x8D, 0x0D, 0x02, 0x60];

const soundLoad = [
	// Offset 0x000000B9 to 0x00000107
	0x8D, 0x01, 0x02, 0x0A, 0xA8, 0xB9, 0x27, 0x82, 0x85, 0x00, 0xB9, 0x28,
	0x82, 0x85, 0x01, 0xA0, 0x00, 0xB1, 0x00, 0x8D, 0x02, 0x02, 0xC8, 0xB1,
	0x00, 0xAA, 0xC8, 0xB1, 0x00, 0x9D, 0x1B, 0x02, 0xF0, 0x20, 0xC8, 0xB1,
	0x00, 0x9D, 0x21, 0x02, 0xC8, 0xB1, 0x00, 0x9D, 0x33, 0x02, 0xC8, 0xB1,
	0x00, 0x9D, 0x27, 0x02, 0xC8, 0xB1, 0x00, 0x9D, 0x2D, 0x02, 0xA9, 0x01,
	0x9D, 0x45, 0x02, 0x9D, 0x4B, 0x02, 0xC8, 0xAD, 0x01, 0x02, 0x9D, 0x15,
	0x02, 0xCE, 0x02, 0x02, 0xD0, 0xC9, 0x60
];

const playFrame = [
	// Offset 0x00000108 to 0x00000132
	0xAD, 0x00, 0x02, 0xD0, 0x25, 0x20, 0x1D, 0x80, 0xA2, 0x00, 0xBD, 0x1B,
	0x02, 0x29, 0x01, 0xF0, 0x11, 0xDE, 0x45, 0x02, 0xD0, 0x09, 0xBD, 0x4B,
	0x02, 0x9D, 0x45, 0x02, 0x20, 0xB3, 0x80, 0x20, 0x8D, 0x81, 0xE8, 0xE0,
	0x06, 0xD0, 0xE3, 0x20, 0xC2, 0x81, 0x60
];

const fetchByte = [
	// Offset 0x00000133 to 0x000001E0
	0xBD, 0x27, 0x02, 0x85, 0x00, 0xBD, 0x2D, 0x02, 0x85, 0x01, 0xA0, 0x00,
	0xB1, 0x00, 0x10, 0x68, 0xC9, 0xE0, 0x90, 0x23, 0xC9, 0xF0, 0x90, 0x32,
	0xC9, 0xF4, 0x90, 0x42, 0xBD, 0x1B, 0x02, 0x29, 0xFE, 0x9D, 0x1B, 0x02,
	0xBD, 0x21, 0x02, 0xC9, 0x02, 0xF0, 0x04, 0xA9, 0x30, 0xD0, 0x02, 0xA9,
	0x80, 0x9D, 0x33, 0x02, 0x4C, 0x52, 0x81, 0x29, 0x7F, 0x8C, 0x01, 0x02,
	0xA8, 0x9D, 0x4B, 0x02, 0x9D, 0x45, 0x02, 0xAC, 0x01, 0x02, 0xC8, 0x4C,
	0xBF, 0x80, 0x29, 0x0F, 0x8D, 0x02, 0x02, 0xBD, 0x33, 0x02, 0x29, 0xF0,
	0x0D, 0x02, 0x02, 0x9D, 0x33, 0x02, 0xC8, 0x4C, 0xBF, 0x80, 0x29, 0x03,
	0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x2A, 0x8D, 0x02, 0x02, 0xBD, 0x33, 0x02,
	0x29, 0x3F, 0x0D, 0x02, 0x02, 0x9D, 0x33, 0x02, 0xC8, 0x4C, 0xBF, 0x80,
	0x8D, 0x02, 0x02, 0xBD, 0x21, 0x02, 0xC9, 0x03, 0xD0, 0x03, 0x20, 0x61,
	0x81, 0xAD, 0x02, 0x02, 0x8C, 0x01, 0x02, 0x0A, 0xA8, 0xB9, 0x29, 0x82,
	0x9D, 0x39, 0x02, 0xB9, 0x2A, 0x82, 0x9D, 0x3F, 0x02, 0xAC, 0x01, 0x02,
	0x20, 0x77, 0x81, 0xC8, 0x98, 0x18, 0x7D, 0x27, 0x02, 0x9D, 0x27, 0x02,
	0x90, 0x03, 0xFE, 0x2D, 0x02, 0x60
];

const doNoise = [
	// Offset 0x000001E1 to 0x000001F6
	0xAD, 0x02, 0x02, 0x29, 0x10, 0xF0, 0x08, 0xAD, 0x02, 0x02, 0x09, 0x80,
	0x8D, 0x02, 0x02, 0xAD, 0x02, 0x02, 0x9D, 0x39, 0x02, 0x60
];


const checkRest = [
	// Offset 0x000001F7 to 0x0000020C
	0xB1, 0x00, 0xC9, 0x5E, 0xD0, 0x07, 0xBD, 0x1B, 0x02, 0x09, 0x02, 0xD0,
	0x05, 0xBD, 0x1B, 0x02, 0x29, 0xFD, 0x9D, 0x1B, 0x02, 0x60
];

const setTempPorts = [
	// Offset 0x0000020D to 0x00000241
	0xBD, 0x21, 0x02, 0x0A, 0x0A, 0xA8, 0xBD, 0x33, 0x02, 0x99, 0x05, 0x02,
	0xA9, 0x08, 0x99, 0x06, 0x02, 0xBD, 0x39, 0x02, 0x99, 0x07, 0x02, 0xBD,
	0x3F, 0x02, 0x99, 0x08, 0x02, 0xBD, 0x1B, 0x02, 0x29, 0x02, 0xF0, 0x10,
	0xBD, 0x21, 0x02, 0xC9, 0x02, 0xF0, 0x04, 0xA9, 0x30, 0xD0, 0x02, 0xA9,
	0x80, 0x99, 0x05, 0x02, 0x60
];

const setApu = [
	// Offset 0x00000242 to 0x000002A6
	0xAD, 0x05, 0x02, 0x8D, 0x00, 0x40, 0xAD, 0x06, 0x02, 0x8D, 0x01, 0x40,
	0xAD, 0x07, 0x02, 0x8D, 0x02, 0x40, 0xAD, 0x08, 0x02, 0xCD, 0x03, 0x02,
	0xF0, 0x06, 0x8D, 0x03, 0x40, 0x8D, 0x03, 0x02, 0xAD, 0x09, 0x02, 0x8D,
	0x04, 0x40, 0xAD, 0x0A, 0x02, 0x8D, 0x05, 0x40, 0xAD, 0x0B, 0x02, 0x8D,
	0x06, 0x40, 0xAD, 0x0C, 0x02, 0xCD, 0x04, 0x02, 0xF0, 0x06, 0x8D, 0x07,
	0x40, 0x8D, 0x04, 0x02, 0xAD, 0x0D, 0x02, 0x8D, 0x08, 0x40, 0xAD, 0x0F,
	0x02, 0x8D, 0x0A, 0x40, 0xAD, 0x10, 0x02, 0x8D, 0x0B, 0x40, 0xAD, 0x11,
	0x02, 0x8D, 0x0C, 0x40, 0xAD, 0x13, 0x02, 0x8D, 0x0E, 0x40, 0xAD, 0x14,
	0x02, 0x8D, 0x0F, 0x40, 0x60
];