Detect High to Low and Low to High EDGE using GPIO PORT Event

[soumil]

Hi,

I am using the pin change interrupt example provided in the SDK examples. By setting the input sense to NRF_GPIOTE_POLARITY_LOTOHI, the interrupt handler is called and in that i again set the input sense to NRF_GPIOTE_POLARITY_HITOLO so that next time it senses the high to low edge. But it never senses HITOLO. I am not able to find the reason for why this is happening.

Here is a example of the code

nrf_drv_gpiote_init();
nrf_drv_gpiote_out_init = GPIOTE_CONFIG_OUT_SIMPLE(false);
nrf_drv_gpiote_in_config_t in_config;
in_config.sense = NRF_GPIOTE_POLARITY_LOTOHI;
nrf_drv_gpiote_in_init(PIN_IN, &in_config, gpiote_event_handler);

Now in the event handler gpiote_event_handler case GPIOTE_CONFIG_POLARITY_LoToHi gets called in which i perform LED toggling and set the

in_config.sense = NRF_GPIOTE_POLARITY_HITOLO

Now the next time it should sense High to Low Edge but it never goes into the case GPIOTE_CONFIG_POLARITY_HiToLo

What could be the reason for this? I am using S110 and SDK10.

[RK]

Can you please use the code formatting buttons to format code in your posts, they're impossible to read otherwise. I reformatted it for you, took 10 seconds.

Is setting in_config.sense to NRF_GPIOTE_POLARITY_HITOLO all you are doing? Because just changing the value in the structure doesn't change the value in the configuration register which actually controls the transition polarity, it only uses the values in that structure at initialisation time to set up the state.

[soumil]

Thanks for the quick reply. I will keep the formatting in mind. Yes in order to set the polarity i am just doing what you mentioned. Is there any function that i am missing right now to change the polarity.

[RK]

well what you're doing doesn't do anything at all, it just sets a value in a structure which isn't used. So yes there's probably an nrf_drv_gpiote_ function you can call to change the polarity. Check the header file or docs, I don't use the nrf_drv stuff, I just write the registers directly.

[soumil]

Thanks for clearing that up. I will look into it. I think its the nrf_gpiote_event_configure function

[soumil]

Okay so i am using this function nrf_gpiote_event_configure which takes one of the arguments as uint32_t Task-Event index. I am confused on what it is and what should be its value.

[soumil]

nrf_gpiote_event_configure(NRF_GPIOTE_EVENTS_PORT, PIN_IN, NRF_GPIOTE_POLARITY_LOTOHI). Isn't this right?