send value's of 1 byte to a modbus device

In the editor you can see word, dword and float values, but in some apps like a CoDeSys it is possible to configure a smaller variables like 1 byte.

In the Modbus table of PLC with CoDeSys and any other Modbus-compatible PLC all the data stored in the universal table. This table includes bytes, and when you need to get a 16-bit, you just get 2 slots of this table. So, if you have a 16-bit variable in iRidium and need to read it, you just get 2 bytes and parse it to 1 byte + 1 byte by the next way:

CoDeSys:     | FF | FF |  - two separated registers (addresses)
iRidium got: | FF FF | - only one register (address).

iRidium automaticly converting this data from HEX to DEC, so we get | 255 | 255 |
We have to parse this data back to HEX, divide the low and high byte and convert it back to DEC.


IR.AddListener(IR.EVENT_TAG_CHANGE,IR.GetDevice("Modbus TCP"),function(item,value) // listener of tag changes for ModBus TCP 
	if (item == "Feedback 1") //set the name of register which should be parsed
		// It was DEC value made of 2 bytes in the string format
		var dec2byte = "27542"; 
		// convert it to number, and then in string of 16-bit 
		var hex2byte = parseInt(dec2byte).toString(16); 
		// get the first byte from the string 
		var hexfirst = hex2byte.charAt(0) + hex2byte.charAt(1); 
		// get the second byte drom the string
		var hexsecond = hex2byte.charAt(2) + hex2byte.charAt(3); 
		// get the DEC number from the HEX bytes in string  
		decfirst = parseInt(hexfirst, 16); decsecond = parseInt(hexsecond, 16);  
		IR.Log(decfirst); // first byte
		IR.Log(decsecond); // second byte

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