Might have missed an obvious method when researching this but here goes.
I do a lot of Time of Flight experiments and so had to design a system to calculate the time at which I get a signal relative to a trigger using 2 channels on a counter card. As multiple events may occur after one trigger it has to measure the time taken (on the order of nano - microseconds) for each signal event relative to a trigger. If you have only one event occurring after each trigger you can use 2 edge separation but for multiple events it becomes harder.
I have a solution but it involves treating the onboard clock as the signal for each channel and treating the actual signal as a clock finding the 'absolute' time of each pulse and then subtracting, whilst accounting for the 32 bit clock restarting etc. Having a multiple edge separation function would make it easier.
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