How to properly handle incoming TCP/UDP data

@Gordon,

I have a minimal nodejs app that extracts the data from the audio mixer. I was way off in the total number of bytes - the real count is actually 67,786 bytes for the entire state of the mixer. Here is the code that successfully got the message dump (obfuscated IP address):

let net = require('net');

let tcpSocket = net.Socket();

let mixerIpAddress = "169.254.0.1";	// A&H Qu Series Mixer IP
let tcpPort = 51325;				// ...and port
let totalLength = 0;

let sysExAllCall = new Uint8Array([0xF0,
	0x00, 0x00, 0x1A, 	// Allen & Heath
	0x50, 0x11,			// Qu series 
	0x01, 0x00,			// Major/Minor version
	0x7F, 				// All MIDI channels
	0x10,				// ??
	0x00,				// LSB is iPad bit, zero to disable requiring ActiveSense
	0xF7]				// All-Call
);

function tcpConnect(details) {
	tcpSocket.connect({port: tcpPort, host: mixerIpAddress}, function() {
		console.log("...connected!");

		tcpSocket.on('data', tcpOnMessage.bind(this));
		tcpSocket.on('close', tcpOnDisconnected.bind(this));

		// inform the Qu that we want telemetry from the device
		tcpSocket.write(sysExAllCall);

	}.bind(this));
}

function tcpOnMessage(chunk) {
	totalLength += chunk.length;
	console.log("chunk length is " + chunk.length + ", totalLength is " + totalLength);
}

function tcpOnDisconnected() {
	console.log('client disconnected');
}

// Get connected
tcpConnect();

I've attached the file that represents the data dump (and there is no missing data from what I can tell). The data dump is a file of space-separated hex values, each representing a byte received from the mixer. At the very end, you'll see a few 'fe' single-byte messages, which is the MIDI ActiveSense byte sent once-per-second by the device. The fact that only 'fe' is being sent at the end of the data means the mixer has completed its dump of NRPN and SysEx data.

I dumped the messages as they arrived - no buffering or messing with the data. Each newline represents the end of the data for that particular message. If you need the file in a different format, let me know and I'll see what I can do.

Edit: how fast can the wifi go? For my project to work, it's gotta be pretty close to real network speeds. I saw 13Mbps was being mentioned on the internet - is that possible?

1 Attachment

• node-nrpn-hex.txt