QN908x PB00 GPIO input with digital XTAL?

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QN908x PB00 GPIO input with digital XTAL?

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Contributor IV

I'm having a lot of trouble getting PB00 to behave as expected.  I'm trying to set it up as a wakeup interrupt that's pulled down by an external device.

It always shows .8V or so and not a solid high or low.

So far, I have set the following:

32k External clock

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PB00 Input, pulled up.

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XTAL32K_INJ = 1 (external digital clock)

PB00_AE = 0 to disable analog function on PB00

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What am I missing?  Is there some sort of limitation on this pin when PB01 is set to XTAL32 IN?

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Contributor IV

I think I found my answer in AN11996:

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It looks like the MCU does not support GPIO usage of XTAL32_OUT pin with square wave clock injection.

Sure would be nice if this was mentioned in the data sheet.

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