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I thought that Port C data lines came up in High-Z mode till I got around to setting DDR and output registers. It doesn't appear that this is the case. I'm trying to force bit 15 of port c low after reset (before and during the NB 2 sec startup delay) using a 10K pulldown and also bit 14 high using a 10K pullup. Bit 14 pulls up successfully but bit 15 appears to remain at High-Z until the 2 sec startup delay is done and the code sets the I/O port ddr and data register. Anybody know what's going on.

Hi,

What processor are you using? It sounds like the MCF5272. This processor is strange in the fact that after reset it has pull-up resistors on all GPIO signals until the ddr register is written... from the MCF5272UM:
"To avoid indeterminate read values and reduce power consumption, internal pull-up resistors are active immediately upon reset, and remain active until the corresponding port direction registers are programmed."

Since the pin you are trying to pull-down appears to be in hiz, I bet they are using close to 10K for the internal pull-up resistors. Try using a 1K or 2K pull down instead.

-Larry

Tough to answer without knowing what processor/platform you are using.