9174 triggered pulse output and analog input sync

[VdG]

Hi,

 i have a 9174 cDAQ with a 9215 analog module and a 9401 module. I wonder if this configuration is suitable for my purpose : a extern digital trigger is sent to the system to trigger a analog input task, trigger a pulse generation, with another counter counting trigger events. Using two counters on 9401, it seems i have no terminal left to input my trigger signal. The DAQmx trigger vi doesn't show the counters inputs in the signal list ; and if i select a PFI line, an error says that the line is already in use...Do i have missed some obvious solution ? Do have i to change my 9401 to a 9402 ?

Thanks for any help,

Vincent

[John_P1 · Accepted solution]

Hi Vincent,

So it sounds like you need a single line to be used as an input for trigger events, and another line to be used to output a pulse generation.  This should indeed be possible, since the 9401 has 8 lines that are nibble configurable (i.e. lines 0:3 could be configured as inputs, while lines 4:7 could be outputs, or vice-versa).

However, one big caveat with the 9401 is that the lines should be reserved before either task is started.  This is a limitation of how the line direction is implemented in hardware, and is a common issue that customers run into when using the 9401.  Explicitly reserving your tasks before starting should fix the behavior if this is indeed what you are seeing.

Best Regards,

[VdG]

Thanks John,

    i didn't know about the reserve function...and i don't get the error anymore !

Vincent