Multithreading support with xTaskCreate

[marvindinneweth]

I want my wifi connection to listen in a separate thread? How can i do this?

[copercini]

Check this out: https://github.com/espressif/arduino-esp32/blob/master/libraries/WiFi/examples/WiFiClientEvents/WiFiClientEvents.ino
https://github.com/espressif/arduino-esp32/blob/master/libraries/WiFi/examples/WiFiIPv6/WiFiIPv6.ino
https://github.com/copercini/esp32-iot-examples/blob/master/WiFi_nonBlocking/WiFi_nonBlocking.ino

You can manage your wifi connection without block the main Sketch

see the functions:
wifiOnConnect
wifiOnDisconnect
wifiConnectedLoop
wifiDisconnectedLoop

[me-no-dev]

what do you mean by "listen on another thread"?

[marvindinneweth]

I want to have a different thread where a little rest api is running and responds to get requests. This intirely separated from the main loop.

[whatnick]

You might be better served using the RTOS port for the ESP32 which has a clear concept of threads, rather than abstracted like Arduino. https://github.com/espressif/ESP31_RTOS_SDK

[igrr]

@whatnick what makes you think that this Arduino core is bare metal? It runs on top of FreeRTOS.

[whatnick]

I meant as threads explicitly exposed, rather than abstracted away in Arduino land.

[me-no-dev]

@whatnick nothing is abstracted ;) Arduino runs in one thread and you are free to spin another one or more if you need to. API is exactly the same... as @igrr said, Arduino on ESP32 runs on FreeRTOS

[whatnick]

What would be the concrete answer to the above ? A threaded webserver sample ?

[me-no-dev]

@whatnick so you want an example? I'm not quite sure what the issue is here?
Again, Arduino runs on top of RTOS and the specific RTOS is: https://github.com/espressif/esp-idf

[whatnick]

An example would be great or specific API docs for accessing the threading.h related functions. Otherwise I will read the samples above and adapt. On 18 Mar 2017 09:35, "Me No Dev" <notifications@github.com> wrote: @whatnick <https://github.com/whatnick> so you want an example? I'm not quite sure what the issue is here? Again, Arduino runs on top of RTOS and the specific RTOS is: https://github.com/espressif/esp-idf — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#228 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAd_hET0uOzps78U4Ov8moy43m01R8rOks5rmxHUgaJpZM4MKFVw> .

[forthlightning]

Not sure about threading.h but freertos has tasks which probably satisfy what you want to do.

I'm on freertos.org all day, here is the task API call that esp-idf uses: http://www.freertos.org/a00125.html

A task has to be of the form

void do_thing_task( void* p ) // gotta have a void pointer as parameter even if unused
{
while( true ) // gotta have infinite loop
    {
        // do things
        vTaskDelay( 1000 / portTICK_PERIOD_MS ) // wait / yield time to other tasks
    }
}

Then you start it with

xTaskCreate( 
&do_thing_task,        // function
"do_thing_task",       // name
 2048,                 // stack
NULL,                  // void* to input parameter
 10,                   // priority 
NULL                   // task handle 
);

[baldram]

This is a really interesting topic. To clarify my doubts I would like to ask by showing example.

Since arduino-esp32 is built on top of FreeRTOS, does it mean it is possible to call xTaskCreate directly from *.ino code? Is there a sufficient API for doing that?

It would look somehow like this example then:
https://github.com/feilipu/Arduino_FreeRTOS_Library/blob/master/examples/Blink_AnalogRead/Blink_AnalogRead.ino

Is it possible with arduino-esp32 ?

[hakuren]

Check out this example by @copercini
https://github.com/copercini/esp32-iot-examples/blob/master/multiloop/multiloop.ino