RE: What is the point of app_scheduler.h in the ble eddystone example?

Bjørn Kvaale — Wed, 13 Dec 2017 11:51:12 GMT

Hi Krastanov. The app_scheduler's primary function is to move any processing out of the interrupt handlers and into the main loop. The advantages of this are short interrupt handlers & all interrupts are dealth with ASAP (see link). In the main() function in the main.c file, the scheduler is initialized first. Afterwards, the function app_sched_execute() is run. This function executes all events scheduled since the last time it was called.

Regarding your question: "is the scheduler told to do anything related to ble?": It is true that no BLE activity is directly controlled by the scheduler. But in the eddystone example, the APP_TIMER_CONFIG_USE_SCHEDULER enables scheduling of app_timer to the app_scheduler. So essentially you use the scheduler to cycle through the different eddystone adversting frames. Therefore, you could say that the app_scheduler is indirectly used for BLE advertising.

It might also be useful to take a look at the Nordic Infocenter & this scheduler library link. This devzone case could also be useful, as well as taking a look at the scheduler tutorial.

RE: What is the point of app_scheduler.h in the ble eddystone example?

shibshab — Mon, 11 Dec 2017 07:28:51 GMT

The scheduler is used (as you state) for performing the garbage collection. The app_timer library also uses the scheduler (see the APP_TIMER_CONFIG_USE_SCHEDULER config). No BLE activity is directly controlled by the scheduler.

If you want to remove the scheduler dependency, implement some check in main-context whether or not garbage collection should be done, and change the config of app_timer to not use the scheduler.