"How I can start and stop my PCI-6052E Counters"

[saqib]

I have NI PCI-6052E board which has two counters. I want to calculate the time between one rising edge and the next falling edge of the two square waves directly connected to two counters of the board using internal clock. I want when the rising egde reach the counter,it must start and the comming falling edge stop the counter. and using timmer I will be able to read the time of high pulse of the square wave. How it will be done.

[RobertoBozzolo]

The application ypu're describing is nothing else than pulse width measurements. With your board you should be able to run the Measure Pulse (DAQ-STC).vi, an example that ships with LV, and obtain immediate results. You'll find it in Search Examples >> I/O Interfaces >> Data Acquisition (DAQ) >> Counters >> Pulse Width Measurement.
Roberto