I am using an 'AC32 part and want to use an external clock source for TPM2. I have an open collector driver currently driving that port pin (PTD4/TPM2CLK/AD1P12) and it is pulled up internally. When used just as an input port with the internal pull-up enabled, it works fine (i.e. the pullup works). When used as an external clock input, the pull-up does not seem to be there.
The manual states, "When any pin associated with the timer is configured as a timer input, a passive pullup can be enabled." That sounds like my pull-up should work. My internal pull-up is still enabled, but it does not pull the pin high when configured as TPM2CLK. Any clues?