HOW TO READ NO. of PULSES USING FPGA

[koolslash]

fpga reading ir

HOW TO READ NO. of PULSES USING FPGA(SPARTAN-3).
the IR will generate a pulse at every complete cycle of a DC motor(2400rpm).
now i want to to count the number of cycles in 1 sec.

 

[barath_87]

Use the waveform u obtain from the IR sensor as the clock to your counter running on your FPGA.

Now run another counter with known clock frequency say 100Mhz and make it to count till 1/(100Mhz)=10^8 (U can take any clock freq. suitable to u it is just a 1second timer).

When timer reaches 1second , you will have the rpm in the other counter(with IR sensor o/p as clock)

I think there should be better ways of doing it,for the moment I am able to think this only.