satellite_protocol.js

/*
 * This file is part of the Companion project
 * Copyright (c) 2019 Bitfocus AS
 * Authors: Håkon Nessjøen <haakon@bitfocus.io>, William Viker <william@bitfocus.io>
 *
 * This program is free software.
 * You should have received a copy of the MIT licence as well as the Bitfocus
 * Individual Contributor License Agreement for companion along with
 * this program.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the Companion software without
 * disclosing the source code of your own applications.
 *
 */
var debug  = require('debug')('lib/satellite_protocol');
var Parser = require("binopsy");

var crc8array = [
	0x00, 0x07, 0x0E, 0x09, 0x1C, 0x1B,
	0x12, 0x15, 0x38, 0x3F, 0x36, 0x31,
	0x24, 0x23, 0x2A, 0x2D, 0x70, 0x77,
	0x7E, 0x79, 0x6C, 0x6B, 0x62, 0x65,
	0x48, 0x4F, 0x46, 0x41, 0x54, 0x53,
	0x5A, 0x5D, 0xE0, 0xE7, 0xEE, 0xE9,
	0xFC, 0xFB, 0xF2, 0xF5, 0xD8, 0xDF,
	0xD6, 0xD1, 0xC4, 0xC3, 0xCA, 0xCD,
	0x90, 0x97, 0x9E, 0x99, 0x8C, 0x8B,
	0x82, 0x85, 0xA8, 0xAF, 0xA6, 0xA1,
	0xB4, 0xB3, 0xBA, 0xBD, 0xC7, 0xC0,
	0xC9, 0xCE, 0xDB, 0xDC, 0xD5, 0xD2,
	0xFF, 0xF8, 0xF1, 0xF6, 0xE3, 0xE4,
	0xED, 0xEA, 0xB7, 0xB0, 0xB9, 0xBE,
	0xAB, 0xAC, 0xA5, 0xA2, 0x8F, 0x88,
	0x81, 0x86, 0x93, 0x94, 0x9D, 0x9A,
	0x27, 0x20, 0x29, 0x2E, 0x3B, 0x3C,
	0x35, 0x32, 0x1F, 0x18, 0x11, 0x16,
	0x03, 0x04, 0x0D, 0x0A, 0x57, 0x50,
	0x59, 0x5E, 0x4B, 0x4C, 0x45, 0x42,
	0x6F, 0x68, 0x61, 0x66, 0x73, 0x74,
	0x7D, 0x7A, 0x89, 0x8E, 0x87, 0x80,
	0x95, 0x92, 0x9B, 0x9C, 0xB1, 0xB6,
	0xBF, 0xB8, 0xAD, 0xAA, 0xA3, 0xA4,
	0xF9, 0xFE, 0xF7, 0xF0, 0xE5, 0xE2,
	0xEB, 0xEC, 0xC1, 0xC6, 0xCF, 0xC8,
	0xDD, 0xDA, 0xD3, 0xD4, 0x69, 0x6E,
	0x67, 0x60, 0x75, 0x72, 0x7B, 0x7C,
	0x51, 0x56, 0x5F, 0x58, 0x4D, 0x4A,
	0x43, 0x44, 0x19, 0x1E, 0x17, 0x10,
	0x05, 0x02, 0x0B, 0x0C, 0x21, 0x26,
	0x2F, 0x28, 0x3D, 0x3A, 0x33, 0x34,
	0x4E, 0x49, 0x40, 0x47, 0x52, 0x55,
	0x5C, 0x5B, 0x76, 0x71, 0x78, 0x7F,
	0x6A, 0x6D, 0x64, 0x63, 0x3E, 0x39,
	0x30, 0x37, 0x22, 0x25, 0x2C, 0x2B,
	0x06, 0x01, 0x08, 0x0F, 0x1A, 0x1D,
	0x14, 0x13, 0xAE, 0xA9, 0xA0, 0xA7,
	0xB2, 0xB5, 0xBC, 0xBB, 0x96, 0x91,
	0x98, 0x9F, 0x8A, 0x8D, 0x84, 0x83,
	0xDE, 0xD9, 0xD0, 0xD7, 0xC2, 0xC5,
	0xCC, 0xCB, 0xE6, 0xE1, 0xE8, 0xEF,
	0xFA, 0xFD, 0xF4, 0xF3
];

function protocol() {

}

protocol.SUPPORTED_MAJOR = 1;
protocol.SUPPORTED_MINIOR = 0;

protocol.SA_HEADER_PARSER = new Parser()
	.endianess("big")
	.uint16("signature")
	.uint8("command")
	.uint16("length");

protocol.SCMD_ADDDEVICE_PARSER = new Parser()
  .endianess("big")
  .string("serialNumber", { length: 20 })
  .uint16("deviceId");

protocol.SCMD_REMOVEDEVICE_PARSER = new Parser()
  .endianess("big")
  .uint16("deviceId");

protocol.SCMD_VERSION_PARSER = new Parser()
  .endianess("big")
	.uint8("versionMajor")
	.uint8("versionMinior");

protocol.SCMD_DRAW7272_PARSER = new Parser()
  .endianess("big")
	.uint16("deviceId")
	.uint8("keyIndex")
  .buffer("image", { length: 15552 });

protocol.SCMD_BUTTON_PARSER = new Parser()
  .endianess("big")
	.uint16("deviceId")
	.uint8("keyIndex")
  .uint8("state");

protocol.SCMD_BRIGHTNESS_PARSER = new Parser()
  .endianess("big")
	.uint16("deviceId")
  .uint8("percent");



protocol.SCMD_PING = 0x01;
protocol.SCMD_PONG = 0x02;
protocol.SCMD_VERSION = 0x03;
protocol.SCMD_ADDDEVICE = 0x10;
protocol.SCMD_REMOVEDEVICE = 0x11;
protocol.SCMD_BUTTON = 0x20;
protocol.SCMD_DRAW7272 = 0x30;
protocol.SCMD_BRIGHTNESS = 0x31;



protocol.calcCRC = function (buffer) {
	var crc = 0;

	for (var i = 0; i < buffer.length; ++i) {
		crc = crc8array[crc ^ buffer[i]];
	}

	return crc;
}

protocol.readHeader = function(buffer) {
	var self = this;

	// Not enough data
	if (buffer.length < 5) return false;

	if (buffer.readUInt16BE(0) !== 0x5A7E) { // SATE(lite)
		return -1; // out of sync
	}

	obj = protocol.SA_HEADER_PARSER.parse(buffer);

	return obj;
};

protocol.sendPacket = function(socket, command, data) {
	var self = this;

	if (data === undefined) {
		data = new Buffer('');
	}

	if (typeof data !== 'object' || !(data instanceof Buffer)) {
		data = new Buffer(data);
	}

	var buffer = new Buffer(5 + data.length + 1);

	var header = {
		signature: 0x5A7E,
		command: command,
		length: data.length
	};

	protocol.SA_HEADER_PARSER.serialize(header, buffer);
	data.copy(buffer, 5);

	var crc = self.calcCRC(data);

	buffer[5+data.length] = crc;

	socket.write(buffer);
};

module.exports = protocol;