RE: Can I run the nRF54L15 I2C peripheral SCL in push-pull mode?

hmolesworth — Sat, 07 Jun 2025 02:50:32 GMT

Yes, of course, push-pull works fine. Sadly you will have to fight with the version of nRFConnect which you are using, unless using nRFx.

This is how to normally set (say) H0H1:

    nordic,drive-mode = <NRF_DRIVE_H0H1>;

.. but note: nordic,drive-mode int

"Pin output drive mode. Available drive modes are pre-defined in nrf-pinctrl.h. Note that extra modes may not be available on certain devices. Defaults to standard mode for 0 and 1 (NRF_DRIVE_S0S1), the SoC default, except for the "nordic,nrf-twi" and "nordic,nrf-twim" nodes where NRF_DRIVE_S0S1 is always overridden with NRF_DRIVE_S0D1 (standard '0', disconnect '1')."

Some effort will be required to defeat this, Nordic may supply the relevant notes

Edit: I should add that we found that some slave I2C devices hold SCL low for clock-stretching (to create a delay between byte transfer) without this being explicitly mentioned in the data sheet; that would cause anything other than S0D1 or H0D1 mode to fail with those I2C slave devices.