Introduction to Embedded Linux Part 6 - Add Custom Application in Yocto | Digi-Key Electronics

Linux is a powerful operating system that can be compiled for a number of platforms and architectures. One of the biggest draws is its ability to be customized for an application. Tools like Buildroot, OpenWRT, and Yocto Project help us create custom Linux distributions for embedded systems.

In this video series, we will explore Buildroot and the Yocto Project. We also demonstrate how you might develop applications for embedded Linux. We will not dive into the specifics of how each of these systems work but give you a good starting place so you can read or watch more advanced material about working with embedded Linux.

In this episode, we take the I2C connection a step further and create our own, custom application that reads from the sensor. We write a simple C application that performs read and write operations to the I2C device file (/dev/i2c-1). We read from the sensor’s temperature registers and combine the bytes to create a valid temperature reading in Celsius. We then print the reading to the console.
You are welcome to use a simple “Hello, world!” application instead of reading from the I2C sensor, if you wish.

While we can develop this program on nearly any Linux single board computer with an exposed I2C device (and appropriate driver and device file), the real magic of Yocto comes into play when we want to include our application in our custom image.

In addition to writing a custom application, we also demonstrate how to write a recipe to cross-compile our application during the build process and include it in our image. When we flash this image to our SD card, it will contain a pre-built version of our application in /usr/bin (on the root filesystem).

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[Kravch]

Please dont stop these videos, they are excellent

[moatasemelsayed]

dont stoooop please it is more than excellent, it gives everything we just needed in our career so please keep going and thanks a lot for your effort

[dymastro]

These videos are awesome! thankyou so much Digikey and Shawn! keep it up. btw channels deserves way more views

[Dinkleberg]

I could listen to Shawn talk day. Awesome content, very relaxing the way he makes the videos and explains everything is great. It would be sooo cool if after this series (maybe on another series i hope) Shawn designes his own custom board with a ST micro, DDR3/4 and eMMC or NAND storage and integrate the image he is building rn on that custom board.

[byteslee]

Free knowledge. Wow!
I wish all universities taught students like that 😁🤣😂

[alexscarbro]

An excellent series that is going to be extremely useful during the development of our next line of products.

[vikrammane]

Shawn, you are really a good instructor. And good course content as well.

[davidquezada]

These videos are awesome, I'm so interested in learning more about embedded systems. Thanks a lot for such an amazing content. It's always good to learn those kind of things for new future projects.

[優さん-nm]

why can't I write the program on my PC instead?

[vivekkumar-tukg]

Great video!! please make a video on QT based gui app on linux.

[優さん-nm]

If we use eclipse or yocto sdk, where will that be run? raspberry pi? pc?

[vladimirvakhter]

Thank you a lot! The video series are great!

[romeklomek]

Hi, this is indeed helpful. Could you please make a short video about using cmake project which is in git repo, that is, how to make custom application build and install to the image if the source code of that app is in the git repo and cmake is used to build such app.
Thank you.

[AbdulRehman-eqns]

Hi, Could you please make a video for .bb file for multiple C and H file in application

[bama]

Please one more video hot to add Qt library in yokto and cross compile some gui

[sagarshubham]

Hello Shawn and Digikey, thanks for another great video in the series. For the next video, would you be interested in using the fbtft drivers in the staging directory? It's a great introduction for writing small overlays for tat lcds, and it can be a great addition to any embedded device to have display capabilities without having to rely on stuff like HDMI and DSI. No issues if it's not in the agenda, just wanted to see how you guys will do it for the STM board. All the best for the next video.

[savinposter]

Hello!
Can you make video about gpio ? Or point to some docs that explaining that theme ?
All tutorials that I found in internet are using sysfs. As I sysfs is deprecated now.

[GA]

Is it possible to create a video that shows, how to deploy Poky for a STM32H743... It is not an MPU, but a MCU capable of running Linux if we add external RAM to it and disable MMU in kernel! It is much cheaper that anny kind of SOM.

[GA]

What bothers me with Yocto is that everybody shows how to work on systems that already have a BSP provided by Yocto or someonne. But noone shows how to write your own BSP in order to be able to deploy Poky to e.g. ARM MCU (strong enough to run Linux) and support one of it's key peripherals i.e GPIO or UART.

[x]

All these work just to read a temperature? It will work better with just bare metal. Should consider another proper example for all these work you have done.