data transfer through USB

[vishhh]

hi, all

I have a circuit having TTL pulse output with pulse width in ns.

I want to count these pulses using labview,

I tried with parallel port but it is not giving proper result for high frequency.

So i want to use USB port.

Can i use it? How?

How does "VISA" help me?

I don't have any DAQ board, is it necessary?

Please  anyone solve my problem.

thanks,

regards

vishal 

[Dennis_Knutson]

You've asked the exact same question mulitple times in multiple threads. The answer is still no and you would need a DAQ board of some type to capture a high speed signal, as you have been told before.

[vishhh]

Thank you, Dennis.

I was asking this same question again because i am using parallel port (right now) to interface, but i wanted it to be done using serial port.

Thanks again, and if u find any solution for this without using DAQ then please tell me, b'caus i can't afford it, as i am a student right now.

bye..........

i would ask if any question , further.

regards,

vishal

Message Edited by nirmalvishal on 04-06-2009 03:15 AM

[Dennis_Knutson]

Asking about using the USB port is not at all the same thing as asking about using a serial port. They are two completely different things. If you have an external instrument controllable over an RS-232 connection, you could do it that way. Does your school have any instruments you could just borrow for the experiment?