Is ->ENABLE = 0 good enough or is ->POWER = 0 better for power saving?

[Clem Taylor]

For TWI, SPI and UART is there a significant power savings from powering down the unit when not in use vs just disabling it?

Disabling the unit seems reasonable, but powering it down and having to reconfigure it everytime would be annoying, but I'm willing to do it if it will save some idle power.

I don't have flow control on the UART, but I'm planning to make it bidirectional on startup and then switch over to transmit only after some time so I can safely disable it.

The power register doesn't seem to be used in the SDK7.1.0 code except in the TWI driver where it is used to power cycle the unit to recover from a hang.

So is powering down the functional unit worthwhile or is disabling it sufficient?

[Stefan Birnir Sverrisson]

Hi

Disabling peripherals should be sufficient for them to stop drawing current. There is also discussion on that here. Also, there are some general recommendations for the UART, SPI, TWI on this thread