Connect the GPS-RTK2 with an Arduino Uno R3

[ramsie838]

Hello,

I have an Arduino Uno R3. Its operating voltage is 5V. I want to connect the Arduino to the GPS-RTK2 board via I2C. The operating voltage of the GPS-RTK2 board is 3.3V. I assume that there is 5V at the SDA and SCL connectors.

I supply the GPS-RTK2 board with 3.3V from the Arduino.

Do I need to adjust the SDA connector of the Arduino with a bidirectional level converter to 3.3V to connect it to the SDA connector of the GPS-RTK2 board?

Do I need to set the SCL connector of the Arduino to 3.3V with a bidirectional level converter to connect it to the SCL connector of the GPS-RTK2 board?

How is it with the RTCM port when sending or receiving data over UART? Does a bidirectional level conversion have to take place there?

I already asked this question in the Sparkfun forum but did not receive any replies.

Thank you

[PaulZC]

Hi @ramsie838 ,
I'm sorry nobody answered your question on the Forums. (Tech support are very busy right now.)
Yes, to be completely safe, you do need to shift the voltage level on both the I2C interface and Serial. We have products and hook-up guides to help you do that:
https://www.sparkfun.com/products/15439
https://learn.sparkfun.com/tutorials/pca9306-logic-level-translator-hookup-guide-v2
https://www.sparkfun.com/products/11771
https://learn.sparkfun.com/tutorials/txb0104-level-shifter-hookup-guide
Very best wishes,
Paul