david_1234
Posts: 328
Joined: Mon Jan 01, 2018 2:14 pm

is there a different on I2c between Arduino and PI?

Thu May 07, 2020 8:02 am

Hello ,
I have created a project on the Arduino using 3 I2C devices:
INA219
Oled display
RTC

the project dispaly the time and voltage , when the voltage is to low acoording to my condition.
all devices works on 3.3V , I didn't use any pullups - just connected all the SDA\SCL direct to the Arduino.

this work just great for me for more then 1 week, with out any problems.

I took the same circuit and connect it to PI using ping 3,5 (enable I2C on configuration)...

when I run i2cdetect - I don't see anything
when I disconnect the Oled - I see the RTC and the Ina219
when I try to read them , I get error - when I run i2cdetect again - I don't see any of them..

when I only connect the RTC to the pi - it's working for 3 hours ~ , then stop and I don't see it any more in the i2cdetect
when I connect the Oled usign 3K3 pullups (3.3V) to the SDA\SCL it's shown in the I2Cdetect , but when I try to send to it data - I get error and I don't see the devcie in the I2Cdetect...
I have double check the wires 5 times.

after all this - I have connect all the devcies again to the Arduino - everything is working without any problems .

so there is must be something in the pi setting ? configuration maybe?

mayebe someone that understand the I2C , and can help me ?

Thanks ,

Return to “Troubleshooting”