The nRF52840 supports 2 Master/Slave instances.
Is it possible to configure the nRF52840 as a Master when connected to an I2C bus that has another Master present?
The nRF52840 supports 2 Master/Slave instances.
Is it possible to configure the nRF52840 as a Master when connected to an I2C bus that has another Master present?
Datasheet says "This TWIM is only able to operate as a single master on the TWI bus. Multi-master bus configuration is not supported." (page 427). Two master may lead to unpredictable results.
Hi,
Thank you for the quick response.
I did see that statement but took it to only apply to the circuit diagram shown - hence the term "This TWIM … ".
Elsewhere the datasheet shows that the nRF52 supports two TWI instances where one can be a slave and one a master.
I don't think that they could both be enabled if mapped to the same pins, but could I not map them to different pins and connect those to the same bus?
could I not map them to different pins and connect those to the same bus?
You could - but what would be the point?
Multi-Master would still not be supported.
You definitely can map two masters to different pins and connect to the same bus, but there is no guarantee it will work. Master peripheral may fail/glitch in case of unexpected transmission on the bus.
There is special way to handle multi-master mode in full I2C specification, but for simplicity it is not supported on Nordic devices,
Okay thank you.
I don't think that they could both be enabled if mapped to the same pins
Correct:
I don't think that they could both be enabled if mapped to the same pins
Correct: