How do I stop wifi so that it can be successfully restarted? [SOLVED]
Posted: Sun Dec 20, 2020 1:52 am
I'm trying to build wifi AP and STA modes that I can start and stop at will.
I call esp_netif_init() once, at startup.
Then I start up wifi using code similar to this simplified pseudocode:
And to stop wifi, I do this:
It works great the first time, but subsequent starts fail as soon as any wifi traffic occurs. In the code as shown, it's a crash: If I reduce the amount of teardown/rebuild — for example, if I just call esp_wifi_stop() to stop wifi and call esp_wifi_start() to restart it — the code won't crash, but it will hang as soon as wifi traffic happens, and in hangs in the same place (as far as I can tell) that it crashes in the full teardown/rebuild code.
So what am I missing?
Solution: Add a call to esp_wifi_clear_default_wifi_driver_and_handlers() in the teardown sequence, e.g.,
(Post left in place in case it's helpful to anyone else.)
I call esp_netif_init() once, at startup.
Then I start up wifi using code similar to this simplified pseudocode:
Code: Select all
_espNetif = esp_netif_create_default_wifi_[ap|station]();
esp_wifi_init();
esp_wifi_set_mode();
esp_wifi_set_config();
esp_wifi_start();Code: Select all
esp_wifi_stop();
esp_wifi_deinit();
esp_netif_destroy(_espNetif);It works great the first time, but subsequent starts fail as soon as any wifi traffic occurs. In the code as shown, it's a crash:
Code: Select all
Guru Meditation Error: Core 0 panic'ed (InstructionFetchError). Exception was unhandled.So what am I missing?
Solution: Add a call to esp_wifi_clear_default_wifi_driver_and_handlers() in the teardown sequence, e.g.,
Code: Select all
esp_wifi_stop();
esp_wifi_deinit();
esp_wifi_clear_default_wifi_driver_and_handlers(_espNetif); // <-add this!
esp_netif_destroy(_espNetif);