Moderator: igrr
Erik84750 wrote:Hi McChubby007, used as sinking means connected to 3.3V with pullup. Yet when I use no pullup all outputs do work except the 0, and if pullup is used it starts to oscillate when supposed to be low; I am in the midst of trying to discover its behavior in function of pullups, this story is not ended yet.
If you look at the diagram I attached; there is an led connected to GPIO 0, via 470ohm resistor and 3.3v, so that gpio acts as a sink (led cathode connected to gpio 0). The led acts correctly when I set output on or off (set pin LOW and led on, as it is a sink etc). I have never seen ocsillation but then I have not inspected with a scope, but visually the led is observed as either on or off. The diagram I attached is actually from a lesser known dev board that used to be for sale. Beyond that I never investigated, since it did what I wanted.
Thank you all for your invaluable assistance!