RE: GPIOTE one input pin to few channels

Fred — Tue, 09 Apr 2019 19:32:14 GMT

Were you able to work with the suggested answer below? If so, please accept it as such.

RE: GPIOTE one input pin to few channels

Fred — Tue, 02 Apr 2019 07:22:01 GMT

This is nice, just implemented something like this myself. So, let me tell you how I did this using PPI, a PORT event and COUNTER.

First I configured the GPIO to trigger on both a rising and falling edge using:

nrf_drv_gpiote_in_config_t config = GPIOTE_CONFIG_IN_SENSE_TOGGLE(false);

To be able to start and stop the counter, at least two PPI channels are to be created with the start-task and the stop-task of the counter respectively connected. However, only the start-channel needs to be enabled initially. When the event occurs, this start-channel needs to be disabled and the stop-channel enabled.

However, the PPI does not have tasks to enable or disable channels directly. Instead PPI channel groups can be used to enable or disable a PPI channel. Adding the 'start' channel to one channel group and the 'stop' channel to the other now makes it possible to have a channel disable 'itself' by attaching the fork of the channel to the disable task of the channel group.

The tasks to enable a PPI channel group again I need two additional PPI channels, that are also added to the respective channel groups as illustrated in the final configuration below:

I hope this gives you inspiration ;-)