max frequency on pwm channel 16f88

What is the max frequency output on a 16F88 MCU on PB3 (ccp1), the PWM output? Tell me I can go to 38000Hz.

In the PBP3.0 manual there's a table that shows max frequencies for given oscillator frequencies. For 8Mhz oscillator, this is 489 Hz. Is this true?

I had 38000Hz output from a LabX1 using a 16F887 MCU. I THINK I had 38000 Hz: my hardware circuit was running (and it's supposed to work at 38000 Hz) but I DID NOT measure the frequency.

I want to trigger an IR LED and detect the signal with a standard IR detector chip like a TSOP 18. If I can't do it with PWM, should I, can I, just toggle a IR detector at 38000Hz? (I know, detectors have a certain protocol to understand the signal, but there are some that simply detect a 38000 Hz IR signal without any fancy modulation.

My 16F88 should be putting out 38000 Hz now...it isn't.

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Originally Posted by queenidog

What is the max frequency output on a 16F88 MCU on PB3 (ccp1), the PWM output? Tell me I can go to 38000Hz.

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Very simple, just check the data sheet Table 9-3.

Hi,

Quote:

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In the PBP3.0 manual there's a table that shows max frequencies for given oscillator frequencies. For 8Mhz oscillator, this is 489 Hz. Is this true?

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No, the table in the manual lists the lowest possible frequency obtainable using the HPWM command at the given oscillator frequency.

/Henrik.

Thank you all! I can't believe I've been misreading the PBP3.0 manual wrong all this time regarding the LOWEST usable frequency. It is NOT highest. And there in the spec sheet, in table 9-3 which I've not seen before (because I was just letting the HPWM command take of stuff), is a table of frequencies.

I'm on a roll.

Thanks again guys.

BTW, the numbers in table 9-3 are not the highest PWM frequency that the PIC can attain. It can reach much higher frequencies than those stated - depending on the resolution you want.