Access sbRIO/cRIO Built-in Serial Port from FPGA

Issue Details

• My Single-Board RIO/CompactRIO has a built-in RS-232/RS-485 port, which I would like to access from FPGA, however, it does not show as an available resource in Project Explorer. Is it possible to access it through FPGA?
• I have an RS-232/RS-485 device that I need to send a command and receive data from. I have this working on the scan mode, can I use the external serial port to communicate with the FPGA?

Solution

Built-in Serial ports of cRIO or sbRIO cannot be directly accessed through FPGA. These ports are accessible only from Real-Time section, where they show up as a standard VISA resource. It is recommended to use Serial VIs and functions to communicate with devices connected to those ports. Additional functions are also available in the VISA palette .

If your application requires serial communication to be implemented on FPGA, there are several ways to do it, however additional hardware may be necessary:

• You can use 987x C-Series Modules that come equipped with additional Serial Ports, that can be programmed and accessed by FPGA Interface.

• You can also try to implement serial communication on NI FPGA using standard Digital Inputs and Outputs.