controlling USB-ERB24

[DAS]

We want to control a USB-ERB24 using a software platform that will be controlling another instrument. The software can send commands to a com port. 

Our question is: when the USB-ERB24 device is installed, does it emulate an rs232 serial port (i.e., a com port)? Put another way, can our software open the appropriate com port and then send text strings to that port to open and close the relays?  If so, is there a manual or information on how to do this?

[DAQman]

Hello,

The USB-ERB24 does not emulate a COM port device. Instead, there is a programming interface that can be used to control it. 

Best regards,
John

[DAS]

Thanks for the response JRys. Do you have any documentation on the programming interface that describes how it works (e.g., a manual) that I can look at?

[DAQman]

Refer to the UL Help document: https://www.mccdaq.com/pdfs/manuals/Mcculw_WebHelp/ULStart.htm

The USB-ERB24 mostly uses either the cbDOut or cbDBitOut function. If you're using Python, the functions are d_out and d_bit_out. If you will be using cbDOut, it writes to selected groups of relays. The first eight is known as FIRSTPORTA, the second eight is FIRSTPORTB, and the last eight is broken into two as FIRSTPORTCL and FIRSTPORTCH. The cbDBitOut function uses FIRSTPORTA and relays numbering 0 to 23. 

Best regards,
John