NetBurner Community Forum

Hi,

I am trying to configure J2[35] as a high z input using the following snippet of code:

J2[35].function(PINJ2_35_GPIO); //External Fermat Reset
J2[35].hiz();


This pin in our design is left floating but after using a scope and multimeter it looks like it either drives or is being pulled high. I've taken some measurements and it looks like its not being pulled up to VCC using a resistor (impedance between J2[35] and VCC = ~2Mohms). Is there an explanation for this? Do the netburner modules have some sort of internal pull enabled when hiz() is called on it?

Thanks!

The J2[35] pin of the module is directly connected to the LTPUODIS or J14 pin of the MCU. This signal is not connected to any other circuitry on the NetBurner module.

According to the MCF5234EC (electrical specifications manual):

All pins which are configurable for GPIO have a pullup enabled in GPIO mode with the exception
of PBUSCTL[7], PBUSCTL[4:0], PADDR, PBS, PSDRAM.

From the DC Electrical Specifications section:
Weak Internal Pull Up Device Current, tested at VIL Max. minimum –10uA, typical not listed, maximum 130 μA.