8-Channel DPDT commands not working via RS232

Using ZRS-A RS-232 Communications Module with the Industrial Relay Controller 8-Channel DPDT + UXP Expansion Port, the API commands don’t work even though they appear to be received via lit channel lights; howeer, the commands do work via Base Station Software, USB, COM port. e.g. to Turn On Relay 2 in Bank 1, I’ve tried sending “AA03FE6D0119”, “170 3 254 109 1 25”, and “170,3,254,109,1,25” which turns on R2 light yet the relay is not changed and no response is received.

Any suggestions on how to troubleshoot this issue would be greatly appreciated.

Hi Sanderson,

The data will need to be sent as byte values instead of string values. i.e. in most cases something like:
will send the ASCII character codes for the string instead of the bytes you’re intending.

How to define the command as a byte array is a bit different for each language, but in Python you can use something like:
command = bytearray([170,3,254,109,1,25])

Some languages you have to use something like this:
command = [0xaa, 0x03, 0xfa];
They default values without quotes that start with 0x as bytes.

Hmmm… It was my understanding that Tibbo BASIC/C converts the hex to binary but perhaps I was wrong. I’ll dig deeper into the docs.