Author Topic: PWM measuring accuracy  (Read 12636 times)

CMS

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PWM measuring accuracy
« on: March 26, 2007, 10:02:43 PM »
If I have a PWM input at 500hz into one of the HSC inputs, what sort of accuracy will I get in measuring the Duty cycle?

Many Thanks

CMS

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Re:PWM measuring accuracy
« Reply #1 on: March 26, 2007, 10:22:16 PM »
Don't use HSC, use PMON inputs and you can measure down to 1 microsecond resolution the pulse width and pulse period, then multiply the 100 and divide pulsewith by pulse period to obtain % duty cycle with 1% resolution. If you pre-multiply by 100000 then you can get duty cycle between 0.000 to 100.000%, i.e. 0.001% resolution.


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CMS

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Re:PWM measuring accuracy
« Reply #2 on: March 26, 2007, 10:30:15 PM »
Thanks once again for your support

Much appreciated