NI9403 source terminal not found

[Bertrand_ENAC]

Hi,

I'm new as DAQ functions user.

We have written following code for a NI9403 device:

DAQmxCreateTask ("", &pt_tache);
Erreur = DAQmxCreateDIChan (pt_tache, "cDAQ1Mod1/port0/line12", "", DAQmx_Val_ChanPerLine);
Erreur = DAQmxCfgSampClkTiming (pt_tache, "OnboardClock", frequence, DAQmx_Val_Rising, DAQmx_Val_FiniteSamps, nb_mesures);
Erreur = DAQmxCfgDigEdgeStartTrig (pt_tache, "cDAQ1Mod1/port0/line12", DAQmx_Val_Falling);
Erreur = DAQmxReadDigitalU32 (pt_tache, nb_mesures, 10.0, DAQmx_Val_GroupByChannel, data, 5000, &nb_mesures_lues, 0);

The last line generates the error:

"Source terminal to be routed could not be found on the device".

We cannot find the reason why it is not working. Maybe a very basic error but we cannot figure it out.

[John_P1]

The error should be coming from DAQmxCfgDigEdgeStartTrig (not the last line but the next-to-last).

You can't use the digital input lines of the 9403 as the source for a start trigger (see Digital IO Considerations for C Series Devices).  It is a serial module which does not provide direct routing to the chassis backplane which is necessary for timing/triggering signals.

Best Regards,