How do i collect pulse frequency at under 1 pulse/sec?

KERBS

The project I am working on involves·receiving pulses from a slowly rotating shaft and converting the frequency of incomming pulses to real world units.· I have a hall effect sensor monitoring shaft rotation and the shaft will turn from 20rpm to· 150rpm.
So pulse output will be from 1 pulse/ 3 seconds to just over 2pulses/second.· The code for the stamp will also be counting accumulating pulses and out putting information to a LCD. I would like to have the LCD updated at least every 2 seconds.· does anyone have any Ideas or tricks to collect incomming pulse rate at very low frequencies.· I've tried "pulsin", but I can only get it to work down to about 5 pulses/sec. Under that and it drops out. "Count" slows everything down dramaticly.·

AlWilliamsAWC

Consider using a PAK-VII (http://www.awce.com/pak7.htm). Another idea: if you are using a BS2P, I wonder if you could do something clever with the polling feature? That would allow you to detect changes you were not immediately looking for (as long as you checked twice as often as your rate). Maybe. I haven't tried that but it might be something to explore.

Regards,

Al Williams
AWC
Easy RS232 Prototyping
http://www.awce.com/rs1.htm
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