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Showing posts from May, 2011

Frequency counter in VHDL (Synthesizeble)

Its Done...!! The Frequency Counter or Measurer is ready. You can measure any I/P frequency from 3Hz to 95KHz i.e. (95,000 Hz for DE1 board Cyclone II FPGA).(This can be diffrent for difrent FPGAs according to their propogation delays and other time factors). Above this value the FPGA gets unstable and show at-random values.

There are 3 levels of Accuracy
Hz.(displayed value) x 10 Hz.(displayed value) x 100 Hz.  I have put a reset button, which is Pushbutton when clicked initiate the frequency measurement process. It then holds the value for user to read.