Arduino Nano 33 BLE Wire speed

Using Arduino Networking, Protocols, and Devices
#1

The Nano 33 BLE uses the Nordic nRF52840 chip. This is capable of running the I2C interface at the following speeds: 100, 250 or 400kHz.

By default, using the WIre library, I can get a 100kHz clock. However if I program any of the other standard values I get a clock of about 200kHz. Is this a known bug?

Martin

#2

My bad: I had forgotten that I2C slaves can pull the SLCK line down to slow down the transfer (aka clock stretching). The default pullups on the board are 18K and this looks like a slow slave. Decent pullup fixes the issue.

#3

This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.