ESPnow two way communication : SCL and SDA pins

Q&A Forum › Category: ESP32 › ESPnow two way communication : SCL and SDA pins

I am working on getting ESPnow working with two Heltec ESP32 boards.
The boards that I have , have built in OLED displays. The SCL and SDA pins are different
than than for the stand alone OLED’s,
My question is , how do I change the IO pin numbers in the code? I can’t find any variables that reference them.
Thanks
Mike

6 Answers

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Sara Santos Staff answered 3 years ago

Hi.
Take a look at this tutorial: https://randomnerdtutorials.com/esp32-i2c-communication-arduino-ide/
Check this specific section:

Use Different I2C Pins with ESP32 (change default I2C pins)

I hope this helps.
Regards,
Sara

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Michal Smialowski answered 3 years ago

Thanks Sara that should be a big help.
Thanks for the quick reply too.
Mike

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Michal Smialowski answered 3 years ago

I looked at the code for espNow_sender and espNow_receiver.
Neither of these have an “include” for wire.h
The two includes are esp_now.h and wifi.h
Where should I look now for changing the pin assignment?
tnx
Mike

0 Vote Up Vote Down

Sara Santos Staff answered 3 years ago

Hi.
Simply, include the wire.h library in your code:

#include <Wire.h>

Then, you can use the functions shown in the tutorial to use different I2C pins.
Regards,
Sara

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Michal Smialowski answered 3 years ago

tnx , I wouldn’t have thought of that.
Mike

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Sara Santos Staff answered 3 years ago

Then let me know if you made it work.
Regards,
Sara