Best way to measure time between two pulses

[hugoxp1]

Hi,

Can you help me decide what is the best way to have the time elapsed between two pulses (picaxe 20X2 or picaxe 18M2)?

Every pulse as a 1ms duration, and I think I can have up to 5 pulses per second.

I was considering to use the count command but if I use count C.1, 5000, w1, I only be able to know how mutch pulses occurred.

I think I will use setint and timer command, but will be the 1ms enough to trigger the interrupt? and can picaxe 20x2 or 18M2 deal with up to 5 interrupts per second?


thank you

(this post is related with: http://www.picaxeforum.co.uk/showthread.php?t=16542)

 

[westaust55]

The pulsein command is also an option.
If the pulses are low to high (and back to low) the use the state keyword accordongly. If State is set to 0 then it will measure from a high to low transition and so measure the low period.

If the pulses are always exactly 1ms and you want leading edge to oleading edge then just add 1 msec.

You need to consider whether the pulses are relatively regularly spaced in time.
At 5 per second that is an average of 200 ms between each so a clock speed of 4MHz (with up to 600ms between two pulses) will be okay and tentatively 8MHz will also be okay unless (with up to 300ms between 2 consecutive pulses.