Pin questions

All ESP32 boards running MicroPython.
Target audience: MicroPython users with an ESP32 board.
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liudr
Posts: 211
Joined: Tue Oct 17, 2017 5:18 am

Pin questions

Post by liudr » Thu Jul 12, 2018 7:24 pm

I am trying to understand pin functions and mapping of ESP32 and need some help. have the following questions:
1. GPIO 37 and 38 or sensor_capp and sensor_capn. These pins are not on the WROVER module's breakout pads. They are probably under the metal cap and have the 270pF caps on them as indicated in the WROVER schematics. Am I correct?
2. GPIO 36 and 39 or sensor_vp and sensor_vn. Since they are coupled to 37 and 38 by these caps, should I still use them for general purpose inputs?
3. Can someone help me understand how IO_MUX and GPIO_Matrix work together to map certain features to pins? I understand that analog inputs and some SD card interfaces and UART0 are attached to pre-determined GPIO pins by IO_MUX. There is no way to, say, map ADC1_CH0 to any pin other than GPIO 36 etc. but there are many choices of GPIO pins when mapping, say, UART1 TX RX pins. How?

fdufnews
Posts: 76
Joined: Mon Jul 25, 2016 11:31 am

Re: Pin questions

Post by fdufnews » Fri Jul 13, 2018 5:49 pm

Concerning question 1 and 2 I think can have an answer on the manufacturer forum not this one

Concerning question 3 I think you'll find the answer here

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