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5 votes
Accepted

Polling multiple GPIOs

Turns out that the ground cable between the two microcontrollers had been dislodged. Putting that back in place fixed my problem.
Somnacin7's user avatar
5 votes
Accepted

Sonoff Dual - Where to find GPIOs

Sonoff has only 2 GPIO pins, button 1 and button 2. Other 2 GPIO pins are used for two relay outputs. Refer here I hope this helped.
Adil Saju's user avatar
  • 280
4 votes

Can somebody explain why some pins on Olimex ESP32-EVB cannot be used?

For the ESP32-EVB, most, if not all pins, are used by all of the stuff they pack on the board. If you look at the schematic for that particular board, you'll see that UART0 (GPIO pins 1&3) are ...
profm2's user avatar
  • 41
3 votes

Sonoff Dual - Where to find GPIOs

According to github, Sonoff Dual R2 is the replacement for Sonoff Dual. Compared to the Dual the main differences/improvements for the Dual R2 are: As the second microcontroller has been ...
Sean Houlihane's user avatar
2 votes

Sonoff Dual - Where to find GPIOs

You can find what you need at the bottom of the aforementioned link. Further to this, my advice is that the schematic shows that, apart from the relay, button and LED GPIOs, (which you probably ...
KDM's user avatar
  • 131
2 votes

Can somebody explain why some pins on Olimex ESP32-EVB cannot be used?

This diagram that shows the GPIO pins as not being available is out of date in my opinion. Perhaps generated from the original Rev A of this PCB. I can see no reason why GPIO6, GPIO7, GPIO8 and GPIO11 ...
Sumps's user avatar
  • 21
1 vote
Accepted

How to control the state of GPIO pins on ESP32 Camera from an external python script?

The easy way you can use http request when you detect something, while running the python app, you send a POST request, this link could help you: https://stackoverflow.com/questions/10313001/is-it-...
offgrid8's user avatar
  • 123
1 vote
Accepted

Mongoose OS and button press detection

As it turns out, GPIO pins 34, 35, 36 and 39 are actually GPI - input only and have no internal pullup or pulldown resistors. I switched to a different GPIO with internal pullup and this solved the ...
Jim Archer's user avatar
1 vote
Accepted

How to change dell edge gateway 3001 gpio pin to analog

Not sure if you found the answer you were looking for, but thought I'd actually sign up and give you some pointers since I've just been down this path myself. The tool you need is 'dcc.cctk' which ...
Kieran Welch's user avatar
1 vote

Can somebody explain why some pins on Olimex ESP32-EVB cannot be used?

I’m not sure why you think you can only use GPIO 4 and 36. Many of the pins are wired either to components on the board (e.g. SD card reader, Ethernet, serial-to-USB converter...) or just to specific ...
jcaron's user avatar
  • 2,293

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