User talk:Achims

Modbus Control commands for R6 extension module:

This commands give you the possibility to control the relays on a R6 extension module via a modbus command send as a hex-file in a tcp stack.

It is easy to connect the R6 extension module to the RS485 interface of a Barix device. You have to wire Pin6 (A) and Pin9 (B) of the DB9 connector to Pin2 (A) and Pin3 (B) of the J1 connector on the R6 extension module.

Additional you have to power up the R6 extension module on Pin4 (+) and Pin5 (-) on J1 connector with an external power supply.

The serial settings for the RS485 interface (Serial 2) should set to a baudrate of 19200 Bd, a data bitrate of 8 bits, parity set to even, 1 stopbit, handshake set to RS485 direction control and local port to 502.

Now it is possible to send a hex-file, which includes the modbus command, via tcp to port 502 of the Barix device. This can be done with the NetCat Application (nc ip-barix port < filename).

The table shows the modbus commands to control the relays on a R6 extension module:

		Modbus Address	Single Coil	Address HI	Address LO	Values HI	Values LO	CRC LO	CRC HI
Relay 1	Set	00	05	00	00	FF	FF	CD	AB
	Reset	00	05	00	00	00	00	CC	1B
Relay 2	Set	00	05	00	01	FF	FF	9C	6B
	Reset	00	05	00	01	00	00	9D	DB
Relay 3	Set	00	05	00	02	FF	FF	6C	6B
	Reset	00	05	00	02	00	00	6D	DB
Relay 4	Set	00	05	00	03	FF	FF	3D	AB
	Reset	00	05	00	03	00	00	3C	1B
Relay 5	Set	00	05	00	04	FF	FF	8C	6A
	Reset	00	05	00	04	00	00	8D	DA
Relay 6	Set	00	05	00	05	FF	FF	DD	AA
	Reset	00	05	00	05	00	00	DC	1A

Please note: It is necessary to calculate a crc-check-sum for each command and add it to the command itself.

Here you can find a online crc-calculator: http://www.lammertbies.nl/comm/info/crc-calculation.html

.