I2C pins of nRF52832 Sparkfun breakout board require pull-up resistors?

Question

I am trying to use press buttons via I2C using nRF52832 Sparkfun breakout board. I followed the steps given in nrf52832-breakout-board-hookup-guide and changed the I2C Data and CLK pins to 24 and 25, respectively. I connected these pins and GND of the board to the corresponding pins and scanned for I2C devices. But it gave error = 2 (no I2C device) for all addresses. Should I use pull-up resistors? I would appreciate any help.

Answer 1

Yes pull-up resistors on both SCL and SDA MUST be provided for I2C communication. Please see the following links:-

• Infocenter specification (See very end of section)
• Devzone Question 1
• DevZone Question 2
• DevZone Question 3

I also recommend asking similar questions on Electrical Engineering or directly on the Nordic DevZone as there is higher chance of this being answered quicker.

I hope this helps

Answer 2

Thanks for your reply. I think it depends on the I2C device that we are using. This module has internal pull-up resistors, but it may not be enough for some devices. So, I disabled the internal pull-ups by replacing GPIO_PIN_CNF_PULL_Pullup with GPIO_PIN_CNF_PULL_Disabled for both SDA and SCL pins in the library and used external ones.