generating a TTL pulse continuously with specified frequency

[spark3]

have an SCB-68 E series, and it has digital outputs (which is where I think is where you generate TTL pulses).

I tried signal express to generate a TTL pulse but I'm not sure if I need a "line" or "port", it is being used to send a TTL pulse to a device as a trigger.

So I just chose, port and set it to continuous but it says I need a sample reference clock BEFORE as an input.

All I am asking for is for 

generate a TTL pulse at a specific frequency continuously until I ask for it to stop.

I am also using LabVIEW but can anyone help?

[AnalogKid2DigitalMan]

spark3: 

The SCB-68 is just a connector block. We need to know what model DAQ card is installed in your computer first to determine its capabilities.

Do you need to send just one pulse or a train of them at a given frequency?

-AK2DM

[spark3]

oh ..

the DAQ card used is a PCI-6229

i need a continuous TTL pulse at a frequency that i can variate

btw i found this example in the NI tutorial but i don't think this is a TTL pulse?

thx, i won't be able to test anything for a week (otherwise i would have done a trial and error and keep trying almost random stuff). but i would like to get a solid head start.

thanks for the help in advance!

Message Edited by spark3 on 10-07-2009 01:58 PM

[AnalogKid2DigitalMan]

LabVIEW has a lot of ready to run examples that ship with it.

Under LabVIEW- Help/FindExamples/HardwareInputAndOutput/DAQmx/GenerateDigitalPulses. It will even show if your hardware supports the program.

Have Fun!

-AK2DM

[spark3]

i've been looking at these (but not able to test)

but are they TTL pulses?

i thought it wouldn't be CO Pulse Freq

but digital output.

but i will tell you how everything goes in about a week and thanks in advance!

[AnalogKid2DigitalMan]

Yes, the digital I/O and counter/timers are TTL logic levels, specs here: https://www.ni.com/en-us/support/model.pci-6229.html -AK2DM