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PiTFT plus 2.8" resistive questions
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PiTFT plus 2.8" resistive questions

by judson on Fri Jan 05, 2018 8:44 pm

First off, I think the documentation at https://learn.adafruit.com/adafruit-pit ... i/overview is wrong -- it says "We bring out GPIO #23, #22, #21, and #18 to the four switch locations!", but I think it's gpio's 17, 22, 23, and 27. That's what's printed next to the switches, and matches what I buzzed it out.

Second, I would like to use one of the extra gpio pins on the STMPE610 as a (low speed) analog input, so that I can control the backlight brightness according to room ambient lighting. Can you show me where to find it on the circuit board, and tell me how to read it from a Python program?

Thanks!

judson
 
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Re: PiTFT plus 2.8" resistive questions

by jamessp on Mon Jan 22, 2018 9:39 am

I just found out that the documented PIO pins are wrong, as descried above, by trial and error. (I didn't notice that the correct numbers are printed on the PCB!)

jamessp
 
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Please be positive and constructive with your questions and comments.