How do you setup a start trigger for 6070E counter?

[Tsquared]

There has got to be a way.

[JustinBritten]

The DAQ-STC counter chip, which is found on National Instruments E-series boards, does not have start or stop triggering capability. A start trigger on the STC counter can be roughly emulated by polling a digital line and arming the counter once a high digital pulse is sensed. If a hardware armed start or stop trigger is required for your application, then one of National Instrument's TIO counter boards is your only option. The following link describes the differences between the timer chips found on our boards.

What are the Difference Between the National Instruments Timer Chips?

http://pong.ni.com/public.nsf/websearch/4501544A6B93BF348625672E00755DB9?OpenDocument

Regards,
Justin Britten

Applications Engineeer
National Instruments

[Tsquared]

Thanks for your response. It is very disappointing to learn the DAQ-STC does not have start or stop triggering. Buying a new card is not an option for me. Because of the timing accuracy I am trying to achieve, I don't think software polling will work for me.

Here is an idea I have. I have a 5411 function generator in the same pxi rack. Its output (i believe) can be triggered. I can route its output to the source input of the counter, then configure the trigger to one of the PFI pins using the RTSI bus. The counter will not start counting until the 5411 is triggered. Does this sound like it can be done?

I am attempting it right now, but so far have not been able to get the 5411 to trigger. I am thinking I am not getting the RTSI bus connected corre
ctly. I used select_signal to first connect ND_RTSI_0 to ND_IN_START_TRIGGER, then used select_signal again to connect ND_IN_START_TRIGGER to PFI0. Then used niFgen_ConfigureTriggerSource to set the function generator trigger to ND_RTSI_0. Doesn't work. Only thing I can think of is that I am not getting RTSI_0 conected to the PFI0 pin correctly. Got any suggestions?

[Matt Duff]

We are doing something similar where we send the output of the analog
trigger to the gate of the counter. It seems to work, although we have used
it much yet. Here are some relevant code snippets:

//send signal from start trigger to gate of counter
iStatus = GPCTR_Change_Parameter (iDevice, ND_COUNTER_0, ND_GATE,
ND_PFI_0);

//Tell MIO to use the analog triggering
iStatus = Configure_HW_Analog_Trigger (iDevice, ND_ON, lLowValue,
lHighValue, ND_HIGH_HYSTERESIS,
ND_THE_AI_CHANNEL);

/* Setup for external start trigger into PFI0. */
iStatus = Select_Signal(iDevice, ND_IN_START_TRIGGER, ND_PFI_0,
ND_LOW_TO_HIGH);


We also had to perform a dummy acquisition to get the MIO to set up all the
connections.