How to stop nRF52832 I2C clock?

RE: How to stop nRF52832 I2C clock?

Jared — Thu, 18 Aug 2022 06:49:43 GMT

Yes, the un initialization function will revert the GPIOs back to their default state.

RE: How to stop nRF52832 I2C clock?

snowuyl — Wed, 17 Aug 2022 14:54:50 GMT

Do you mean what I need is just call I2C uninitialized function and don't need to call GPIO function?

RE: How to stop nRF52832 I2C clock?

Jared — Wed, 17 Aug 2022 07:55:33 GMT

Hi,

The GPIOs assigned to SDA and SCL will be configured back to its default state as Input with Input buffer disconnected and no pull.

regards
Jared

RE: How to stop nRF52832 I2C clock?

snowuyl — Wed, 17 Aug 2022 01:58:09 GMT

After calling I2c uninitialized function, i2c in high or low state? Do I need to call gpio function to force it to high or low state?

RE: How to stop nRF52832 I2C clock?

Jared — Tue, 16 Aug 2022 05:36:14 GMT

The clock should be stopped after the transaction has stopped. It would be best to un-initialize the TWI driver after you're done with the transaction to save as much power as possible. How are you determining the state of the clock? Are you measuring the power consumption?

RE: How to stop nRF52832 I2C clock?

snowuyl — Tue, 16 Aug 2022 02:59:11 GMT

Thanks for your reply! I use I2C as communication interface between nRF52832 and analog front-end (AFE). I have power down AFE. Do I need to uninitialize I2C driver for stopping I2C clock for power saving?

RE: How to stop nRF52832 I2C clock?

Jared — Mon, 15 Aug 2022 09:01:15 GMT

Hi,

Un- initializing the driver after the transaction has stopped should be enough.

In some cases, the TWI driver will not stop the clock even after un-initializing the driver. If that is the case, then you're most likely experiencing errata 89, you should then power cycle the peripheral by following the workaround as described here.

regards
Jared

RE: How to stop nRF52832 I2C clock?

snowuyl — Mon, 15 Aug 2022 08:09:19 GMT

devzone.nordicsemi.com/.../5430.i2c.c