NRZI & MLT-3 decoders

gistfile1.js

var code1 = "0010110111011111001001000010110011011100111001101"
var code2 = "1102201100200102001002011102220011020111000220110"

function decodeMessage(message) {
	if (message.length != 49){
		throw new Error("Bad length");
	}
	var ans = [];	
	for (var i = 1; i < message.length; ++i) {
		ans[ans.length] = (message[i] != message[i-1] ? 1 : 0);
	}
	return ans;
}

function fromBitsToAscii(bits) {
	if (bits.length % 8){
		throw new Error("Bad length");
	}
	var ans = "";
	while (bits.length) {
		var code = 0;
		var part = bits.splice(0, 8);
		for (var j = 0; j < 8; j++) {
			code += part[j] ? (1 << (7 - j)) : 0;
		}
		ans += String.fromCharCode(code);
	}
	return ans;
}

var decoded1 = fromBitsToAscii(decodeMessage(code1));
var decoded2 = fromBitsToAscii(decodeMessage(code2));
console.log(decoded1);
console.log(decoded2);