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in general what I want to to do is use an FPGA to replace a set of laboratory equipment that does the same thing (discriminator, logic unit), in order to compare, I have to generate the same output that the discriminator does
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Before you create more work than you need, figure out what you really want. Just because your current lab system generates a pulse, it does not mean you need to duplicate that setup. You may be making things more complicated than needed.
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Thanks for the information, I'm going to read it, and I forgot to tell that the time between events is at least of 50 ns, and I have to study more about synchronous and asynchronous systems, because I believed that if my sampling method used or not a clock defined an synchronous or asynchronous system
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Since the time between events is 50ns, the minimum toggle pulse high or low time is 50ns. You can easily synchronize that signal to a 100MHz clock (10ns period) and generate a synchronous pulse in the 100MHz clock domain. Those pulses can then be counted.
If what you really need is a count of events per second, you could easily create that using an FPGA. For example, every second your FPGA control logic can clear the event count, and start a 1s timer. During the 1s timer period your logic can count events using another counter. When the 1s counter is done, you will have a count of events for that second. You could display that on an LCD. The 1s counter would repeat every second, and the event counter would be cleared every second. The display would show the last 1s total event count.
With that in mind, think about what your current lab setup does, and what you really want. Chances are your FPGA can give you what you want without needing more test equipment.
Cheers,
Dave
Honored Contributor
