PCIe 8430-8 and 8431-8 returning bad data

[neilkgoode]

I have a system with a PCIe 8430-8 and 8431-8 running RHEL9 with the Q1 2025 drivers installed. I have a serial device I am using these with that can be configured for 232 or 422 modes, and testing with both modes I receive data that doesn't make sense from the device. I can try the same device using a USB serial adaptor on the same system, and the data is received correctly. I have tried giving the ports the same config with stty and have tried setting the baud of the NI serial ports using the VISA program to no avail. Has anyone had any experiences like this? Any help is greatly appreciated. I am also using these with the correct cables supplied with the devices.

[Leonard_Gartner]

Hi neilkgoode,

For my understanding of the issue I have some questions:

1. What does bad data mean? In which way is it different from your expected data stream? Do you see a pattern, f.e. a constant offset?

2. How are you reading the serial data from the NI PCI devices compared to the USB devices ? Ideally you would use the same program, except for the drivers which naturally differ for the PCI and USB device of course.

3. What do you configure exactly with stty and/or VISA? Which devices do you configure?

Best regards

Leonard