twi with internal pull-up

[mdido]

Hello, I'm using SDK 15 and softdevice 6.0.

I use the micro as a master and I connected an i2c sensor as slave. I had put external 10 Kohm pull-ups, but I had a low level at around 100 mV. I found that the micro-nordic twi device has internal pull-ups at 13 Kohm, so I removed the external pullups and the zero level was raised to 25 mV. Is it possible to disable internal pullups so I could put the lower external pullp?

Thank you

[Håkon Alseth]

Hi,

 

It is the define nrfx_twim.c::TWIM_PIN_INIT() that enables the internal pull up resistor. Change this to NRF_GPIO_PIN_NOPULL if you are using external resistors.

 

Kind regards,

Håkon