How to Multitask with FreeRTOS (ESP32 + Arduino series)

Run multiple tasks on the ESP32 with FreeRTOS. For instance: blinking two LED's at different intervals or increment two counters at the same time.
A FreeRTOS task is nothing more than a standard C (or C++) function. Nothing fancy, very easy!
Most ESP32's have a dual-core processor, so FreeRTOS will balance your tasks across cores. This technique also works for single-core versions of the ESP32. In that case, FreeRTOS will rapidly switch between tasks, giving the impression that it's multitasking.
⚡️Other videos in this series:
• ESP32 + Arduino
(Everything you need to know about programming the ESP32 by using the Arduino Framework)
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[@portillajoe]

FreeRTOS was a topic that I thought was quite complex but with your explanation I finally understood how to handle it. Thank you.

[@fatheramo1]

I love how I just tried looking for generic Arduino Multitasking and I was so lucky to find this video using an esp32 with platformIO which is a prefect reference for my project.

[@adrianw2972]

Nice Entry into RTOS 👍 May I note that one should not add computation within a print function, especially if using the Arduino IDE. In the above example the count1++ should occur outside (before) the print statement, then the value of count1 can be printed (this goes for count2 also!). To see this issue in action, change the BAUD rate to 115200 and set the second delay (task2) to 200ms. After every few iterations you will see that the print is corrupted. Move the count++ outside of the print function to fix this. It's a very tempting short-cut, but it will bite you! 😄

[@shuaibalghazali3405]

I love this video, simplifies the concepts of RTOS

[@cloudpicrc5076]

freertos is so easy to understand from you vides.I will using it in my projects,thanks.

[@k.k8221]

Thank you man, you are "Simply Explained" .....now I understood, again Tahanks.

[@jonathanrodriguez8219]

Good and simple explanation!!

[@billtsou8071]

This is an amazing tutorial. I've gotten an error because I wrote an infinite loop inside the task with millis() instead of calling vTaskDelay(), which would trigger the watchdog timer and reset the chip. Thanks for your kindness sharing. It does really help me a lot!

[@maximebernard7212]

clean and clear thank you

[@kingsoapvii4273]

Good video bro, you have my respect, +1 like

[@SinanAkkoyun]

Very clean 😍😍😍

[@zerobow9413]

Excellent dude

[@benzemamumba]

Brilliant!

[@dukathneu]

Thanks. That helped!

[@f7p1764]

How to calculate or view somewhere how many bytes is needed to set in task and what is the limits on esp32?

[@handlewithoutsuitcase]

Nice reverb, mate.))

[@ShaffleOne]

Man... Where have you been all this time?? I searched literally everything to learn how to multitask with esp32...

[@Vietnamcamping89]

Cool bro

[@Chris-Brown-]

How did you set it up, what library, add-on etc did you install? Why is it not in Arduino IDE, like the title?

[@TrackAnimatorsMEDIA]

I have a question for you. Do you know of a way to install a OS from a keyboard like the Ensoniq EPS Classic or old Akai MPC drum machines on an ESP 32?

[@henrychan720]

How accurate is vTaskDelay? That is, is it affected by other tasks?

[@yashaskumargb3827]

Please provide link to video where data generated in one task can be transferred to another task

[@tcl78]

It is not clear if i have to install something to make FreeRTOS available. Also, you mentioned ESP IDF in the previous video, what is it? How can i use it? Is it an alternative to the Arduino's Framework? Wouldn't it be better to learn something native to ESP32 instead than using something that was born for a different platform (the Arduino Library) and that perhaps cannot use the full power of ESP32?

[@simplyexplained]

Arduino for the ESP32 is built on top of the “native” framework (ESP-IDF). Everything that’s in IDF, is available from Arduino (including FreeRTOS). Is it better to directly use IDF? Nowadays, yes. The Arduino version is stable, but uses an older version of IDF.

[@ptmoy1]

I have a conceptual question: do you have to install FreeRTOS like you do a regular operating system (e.g., Windows, Ubuntu, etc.) before you can use its functions, or is FreeRTOS just a library in ESP-IDF, and you flash what you use from the library to the microcontroller along with your own code?

[@adrianw2972]

No, you do not. It is not an interpreted language like python or BASIC, the final program is compiled. If you have installed the IDE for the ESP, it will then work

[@wnbrook4220]

Hello, How to put ISRs in core0 ? thanks in advance.

[@hazlamyfaizal9992]

Can someone tell me if i need to download smtg from a library first before able to use this RTOS. The commands dont work for me

[@bascelik91]

Maybe I am wrong and pls correct me. But freertos is included in Arduino library and it supports esp32? I mean this is already builtin library? I guess same lib can be used for arduino boards? thanks :)

[@simplyexplained]

No. Arduino for the ESP32 has been build on top of esp-idf. FreeRTOS comes from idf, not Arduino.

[@billtsou8071]

Yep, like what @Simply Explained said. ESP32 packages should be installed externally. But there is Board Manager in Arduino which reduces a lot of works. Or be more simple, you can directly download the ESP32-packaged version of Arduino on Google.

[@mlsh-azerty]

hmm what🤨 ? how you run freertos without any includes ? and hiw to have both arduino.h ard freertos ??? help 🙃 (trying on esp8266)

[@vjreviewsandiy]

Hi, for development mode, I don't want the task to run continuously. If I change from for(;;) to (int i = 0; i

[@CodeExplorer-tm2ur]

I get this exact same error when even using the codes as is (with my wifi settings of course). I'm starting to think that this is some kind of issue with the chip as mine is Adafruit ESP32 Feather. If i comment out the wifi.begin() function I do not get this error but of course system doesn't do what is supposed to

[@joecox9958]

Very nice! but not sure which IDE you used.

[@adrianw2972]

This will work in the Arduino IDE, just add the ESP32 with the JSON line as explained all over the web.

[@quanyechen4161]

In my board, the `usStackDepth` argument for `xTaskCreate` function is equal or more than 2048, otherwise board will kernel panic.

[@vinhnguyenquang7205]

pls anyone show me how to include freertos. tkssssssss

[@zunairakhalid7358]

can we make Free RTOS based Encrypted Walkie Talkie?

[@AliHussein-bb3ie]

How many tasks can use?

[@annoorkhan4219]

What compiler you are used ? It's not Arduino ide?

[@simplyexplained]

I'm using Visual Studio Code as the editor. Compiling is handled by the PlatformIO plugin.

[@kingsoapvii4273]

I love You

[@djtyros]

What IDE is this, and how can I download it, and link it to my esp32 so I can run/upload code from within this IDE? I find the Arduino IDE lacks AutoComplete. Thanks

[@krillnyetheshrimpguy6152]

it's platformio, it's an extension to Vscode

[@felipefelin8362]

what theme are u using in VScode?

[@simplyexplained]

Quiet light

[@rongarza9488]

Maybe I'm misunderstanding the terminology but this is not parallel processing. It appears to be time slicing instead, bouncing between one task and the other. Try counting from 0 to 99 and then printing on task 1, and counting from 0 to 199 and then printing on task2. If task1 prints twice as often as task2, then you really are parallel processing.

[@simplyexplained]

This depends on the ESP32 you’re using. Most models are dual-core, and if the WiFi is disabled, two tasks will run in parallel. In other cases, FreeRTOS is indeed sharing the CPU time amongst tasks.

[@haritkrishan947]

I don't understand how this has anything to do with the FreeRTOS source code that we download from the website. I have been doing this multi-core computation with the ESP32 for quite some time, but never realised this is considered RTOS programming.

[@ahmadal-tarabeen9253]

Who think that this method is the best method that I can use to generate Signal pattern to an Inverter Mosfet gates ?!

[@marquezchris2210]

6.9$ for DFRobot FireBeetle ESP32 IoT Microcontroller (Supports Wi-Fi & Bluetooth)

[@zyghom]

unfortunately these examples are ok but only when there is no any other process that is running in rtos, i.e. OTA. But when OTA kicks, the ESP32 crashes. So probably this tutorial requires a bit more of explanation how the 2 tasks can work with other tasks without crashing. I would be first to watch it ;-)

[@adrianw2972]

IF you are not using Wi-Fi or BT, then switch them off, otherwise set your application to use only one processor, the wireless stacks take precedence!

[@zyghom]

@@adrianw2972 you are right but esp32 without communication is useless ;-)

[@adrianw2972]

@Zygfryd Homonto quite untrue. I use them in standalone projects, usually with displays. If you wish to use WiFi or BT, simply set your code to use core one only, core zero is used for wireless. And do not use blocking code. I.e. do not use delay, use the FTOS delay functionality etc.

[@zyghom]

@@adrianw2972 some ESP32 are single core - actually I mainly use S2 that is much faster but 1 core only. So I had to use it different way