disabling twi/i2c

[Vandita]

Hey, I am using twi_hw_master.c and twi_master.h libraries for twi and want to disable i2c to save power when not in use. I use the following two lines to disable the i2c:

NRF_TWI1->ENABLE       = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos; 

NRF_TWI1->POWER        = 0;

but it still works. What other steps do I need to take in order to disable the twi peripheral? I'm using nrf51822 on a custom board with sdk9.0. Thanks, Vandita

Code files: main.c latch_i2c.c

[bjorn-spockeli]

The drivers located in the incubated folder are decrepated. Use the nrf_drv_twi_disable function in the nrf_drv_twi driver, please refer the TWI Driver Documentation, found here.

[Vandita]

Hey Bjorn, Thanks for your response. I had earlier tried to use the nrf_drv_twi libraries but faced a lot of issues and moved to the incubated libraries instead. The nrf_drv_twi function takes a TWI instance as an argument and that's not available as I'm using the other libraries.

What other registers need to be written for disabling the TWI? Thanks, Vandita

[bjorn-spockeli]

You'll have to set the following registers:

NRF_TWI1->TASKS_STOP = 1;
NRF_TWI1->ENABLE = TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
NRF_TWI1->INTENCLR = (TWI_INTENCLR_STOPPED_Disabled << TWI_INTENCLR_STOPPED_Pos)| \
                        (TWI_INTENCLR_RXDREADY_Disabled << TWI_INTENCLR_RXDREADY_Pos)| \
                        (TWI_INTENCLR_TXDSENT_Disabled << TWI_INTENCLR_TXDSENT_Pos)| \
                        (TWI_INTENCLR_ERROR_Disabled << TWI_INTENCLR_ERROR_Pos)| \
                        (TWI_INTENCLR_BB_Disabled << TWI_INTENCLR_BB_Pos);

[Vandita]

Hey Bjorn, I tried these statements and still the i2c is working. I have added the code files to the question.

[bjorn-spockeli]

Are you using twi_hw_master.c or twi_sw_master.c?