I've read the MCF52235 ColdFire Integrated Microcontroller Reference Manual from cover to cover and I'm still a bit foggy about the meaning of the "pull-up/pull-down" column in Table 2-1.
The column heading cites Note 2, which says "all signals have a pull-up in gpio mode." I assume this to mean that the device unconditionally activates an internal pull-up for any multi-function pin that is operating as a gpio, but the internal pull-up is not activated for other modes unless there is an entry in the column that indicates otherwise. Is this correct?
All pins that have a gpio function are configured to operate in gpio mode upon reset, and thus all of these pins are pulled up by the internal pull-ups by default. Are the pull-ups active when reset is asserted, or only upon release of reset?
Some pins (e.g., IRQ2) indicate "pull-up" in the column and cite Note 6, which says "for primary and gpio functions only." I assume this to mean that the device activates an internal pull-up, but only when the pin is operating as either gpio or primary function, and in all other cases the pin has no internal pull-up. Correct?
The RSTI pin indicates "pull-up" and cites Note 9, which says "RSTI has an internal pull-up resistor, ..." Based on this, I assume that the TEST and JTAG_EN pins, which indicate "pull-down," have internal pull-downs, and thus it is not necessary to tie them to ground or supply external pull-downs. Correct?
Similarly, RCON indicates "pull-up," which is assumed to mean that it has an internal pull-up, and thus this pin may be left disconnected to permanently disable the ezport. Correct?
