Acknowledging CAN signals with USB-8502/2 and XNET

[CM6666]

Hello,

I have a device which acts as a master on a LIN network, and converts the signals to both CAN and RS-232. 

The RS-232 signals are being read fine by the dedicated software on the computer.

However, the NI-XNET bus monitor only shows the first CAN signal transmitted and none after that. I am told the reason is that the CAN card has not acknowledged (ack) the signal and therefore an error is generated and this frame is repeatedly tried. 

Please let me know if you know how to resolve this issue.

[JefeL · Accepted solution]

In the bus monitor settings, "Listen Only" mode will control whether or not incoming frames will be acknowledged by the chosen CAN interface. If "Listen Only" mode is checked, the selected interface will not issue an acknowledgement.

You can also check the "Bus Error Frames" box to see a frame with ID = 0x0 whose payload indicates the type of errors detected. Byte 3 (zero based) indicates the type of error with 0x3 being an Ack error or lack of acknowledgement. Additional details on special frames can be found here.

[CM6666]

Many thanks Jeff, it was indeed in "Listen Only" mode, so after changing that it is working perfectly.