Author Topic: Simultaneous use of one channel  (Read 8051 times)

Ken Talley

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Simultaneous use of one channel
« on: March 09, 2002, 10:58:21 AM »
Is it possible to use one phycical input by two or more TBASIC functions. For example measure the pulse frequency for PID information and at the same time run a Highspeed counter to function as a totalizer?

Thanks,
Ken
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
Ken

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Re: Simultaneous use of one channel
« Reply #1 on: March 10, 2002, 06:39:51 AM »
Since the PMON (for pulse measurement) and HSCDEF (high speed counter) share the same input pins, it means that they are mutually exclusive. i.e. if a pin is defind for PMON it cannot be used for HSCDEF. The last defined function prevail.

What you can do is to use input 3,4 as PMON to get two channels of pulse width measurement, then connect a wire from pin 3 to pin 5 and use HSCDEF channel #2 for high speed counter measurement.

« Last Edit: March 23, 2004, 11:30:08 PM by support »
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Ken Talley

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Re: Simultaneous use of one channel
« Reply #2 on: March 10, 2002, 08:33:21 AM »
Would it make the most since to do it as you described or is their an accurate way in programming to totalize using frequency verses time.
Ken ???
« Last Edit: December 31, 1969, 04:00:00 PM by 1076562000 »
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Re: Simultaneous use of one channel
« Reply #3 on: March 11, 2002, 09:10:33 AM »
I thought the high speed counter alone is sufficient as a "totalizer" if counting pulses is all you need? Why do you need to measure the frequency for totalizing purpose? Anyway, the frequency measurement
is pretty accurate so if you want to use time x frequency the accuracy is determined by how accurate you can capture the time between two measurement.

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« Last Edit: March 23, 2004, 11:30:27 PM by support »
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