graycatlabs / PyBBIO

A Python library for Arduino-style hardware IO support on the Beaglebone
https://github.com/graycatlabs/PyBBIO/wiki
MIT License
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Pull-ups, pull-down configuration issue #108

Open jonturner53 opened 7 years ago

jonturner53 commented 7 years ago

I've found an apparent issue with the configuration of pullups and pulldowns for the GPIOs. While this seems to work correctly for pins that are configured as inputs, it does not seem to work for pins that are configured as outputs. Specifically, when I configure GPIO1_12 as an output pin with no pullup or pulldown using a simple test program containing the line,

pinMode(GPIO1_12, OUTPUT, 0);

the pins file shows

pin 12 (44e10830) 00000007 pinctrl-single

(and yes, 12 is the correct pin number for GPIO1_12). Note the bits 3 and 4 are both low indicating that a pull-down is enabled. This remains the same no matter what value use in the pinMode call (-1, 0 or 1). Apparently the last argument is being ignored for OUTPUTs.

Is this a bug or a feature?