Delay one D/O line after the other

[joyce]

Hi,

I have a PCI-6014 board, and I would like to use the digital port to generate separate TTL pulses to trigger two different devices simultaneously.

I want the TTL to stay "high" for 3 seconds so I put the Write vi in a loop.

I initially had the port write a 1-D boolean (using two lines), but I discovered that one device (a solenoid) takes about 50ms to charge up, resulting in a lapse between the two devices by 50ms in the beginning and at the end as well.

Thus I have created two separate tasks and give one line a 50ms wait time before it writes. However it doesn't solve the problem.

I am guessing is it because both lines are from the same Port so that I can not generate a delay between them ?

My PCI-6014 board only has Port0.

I am also using both counters on the board so I can't use them.

Thank you very much in advance.

Joyce

[joyce]

hi,

I tried to do the above application using a Digital Waveform, so I can create two signals that look like :

11111100

01111110

So I suppose by assigning appropriate "delta t" I can control the TTL start and duration times, i.e I can switch on the solenoid before the other device.

But the real output signals don't really have the "time" that I assign. They are just a burst of TTLs, not TTL pulses that last 1sec each.

Why doesn't the "Build Waveform" vi give me the real times ? Should I do a buffered writing ?

Thanks so much.

Joyce

[joyce]

I have solved the problem.

Thanks anyway.

PS. I don't know how to delete my own post.

Joyce