''DAQmxBase Error 4294767076: Device identifier is invalid. Source must be on same device as channel

[JMPuc3m]

I want to use the counter channel to generate pulses and use these pulses to trigger the analog acquisition using a usb-6211 card I am using NI-DAQmx Base 15.0 with Linux Scientific. I can generate the counter pulses (see attached C code) in PFI4. I physically wired PFI4 to PFI0 and specify PFI0 as the source for the start trigger of the analog channel. I have actually tried this earlier in Matlab and works fine, but the C code over Linux gives the following error: ''DAQmxBase Error 4294767076: Device identifier is invalid. Source must be on same device as channel.''

I am not sure what this means since the source is in fact in the same device as the as the channel. Software NI Hardware:  USB-6211 device Driver Version :   daqmx base 15  Operating System:  Scientific Linux

[Kevin_Price · Accepted solution]

It's pretty subtle, but the "path" to a terminal such as PFI0 needs to have a leading "/" character.   So, try "/Dev1/PFI0".  This is different from the path to a channel where "Dev1/ai0" was fine.  

I'll bet there's probably a reason for this, though I've never heard it or pursued it.

-Kevin P

[JMPuc3m]

Thank you Kevin