is there a different on I2c between Arduino and PI?

Projects Networking, Protocols, and Devices
1

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

dispaly the time and voltage , when the voltage is to low acording 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 tool 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?

I have ask this question also in th PI forum - they didn't know how to answer it
mayebe here someone understadn better the I2C , and can help me ?

maybe there is a different in the setting\circuit
when I use recieve device (like Oled\LCD)
and when I use sending device (Like DS1307\INA219\sensor)?

Thanks ,

2

all devices works on 3.3V

No, the Arduino doesn't.

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

The Arduino enables the internal pull-ups in the Wire library. So there is a minimal pull-up which usually works for short cables.

maybe there is a different in the setting\circuit
when I use recieve device (like Oled\LCD)
and when I use sending device (Like DS1307\INA219\sensor)?

Each I2C device is receiving and sending, otherwise it won't work on the bus.

If you need more details, post links to the exact used hardware and a wiring diagram!

3

what do you mean by

No, the Arduino doesn't.

?
The Arduino is powered by USB from the computer - if this what you mean.

when I said all is 3.3V - all the I2C devices are connected to the 3.3V from the arduino

I will try now to connect it to 5V -
give it to run a day and retuen with the resualts .

all devcies can work with 2.5-5.5 power in

diymore GY-219 INA219 Current Sensor Module Power Supply Breakout Board Module GY219 I2C Interface for Arduino.

4

The Arduino is powered by USB from the computer - if this what you mean.

The Arduino runs on 5V. If you connect a 3.3V device to it directly you may damage it.

when I said all is 3.3V - all the I2C devices are connected to the 3.3V from the arduino

They may be powered by the 3.3V output of the Arduino but what's with the bus signals?