ethrly-server.js

// console.log(process.argv);

var port = parseInt(process.argv[2]);
if ( !port || isNaN(port) ) {
	console.log('\nPort arg must be int.\n\n');
	process.exit();
}

var status = [0, 0, 0, 0, 0, 0, 0, 0];

require('net').createServer(function(socket) {

	console.log('\nNew connection...');
	// socket.setEncoding('utf8');

	function writeStatus() {
		var dec = 0;
		status.forEach(function(on, i) {
			dec += on * Math.pow(2, i);
		});

		console.log('Writing status: ' + dec);
		var buffer = new Buffer(1);
		buffer[0] = dec;
		socket.write(buffer);
	}

	socket.on('error', function(e) {
		console.log(e);
	});

	socket.on('data', function(data) {
		var cmd = data[0];
		console.log('Incoming data...', cmd);

		if ( cmd == 91 ) {
			// get status
		}

		else if ( cmd == 100 ) {
			// all on
			status.forEach(function(on, i) {
				status[i] = 1;
			});
		}
		else if ( cmd >= 101 && cmd <= 108 ) {
			// one on
			var relayIndex = cmd - 100 - 1;
			status[relayIndex] = 1;
		}

		else if ( cmd == 110 ) {
			// all off
			status.forEach(function(on, i) {
				status[i] = 0;
			});
		}
		else if ( cmd >= 111 && cmd <= 118 ) {
			// one off
			var relayIndex = cmd - 110 - 1;
			status[relayIndex] = 0;
		}

		console.log('New status:', status.join(''));
		writeStatus();
	});

}).listen(port);