Raspberry PI + FreeRTOS + µGFX

[macload1]

Hello guys,

I've actually a working FreeRTOS port (James Walmsley's port updated to version 8.0.0 by myself) and access to the framebuffer of my Raspberry PI (University of Cambridge's explanations rewritten in C by myself).

I would like to add some graphical interface now, and checked out different solutions. My proper library (written several years ago for PIC18 and PIC32) is easy to port, but has only very little possibilities (character display, simple forms like rectangle, circles,... and image support for my proper image format). Many other big graphical libraries are not free.

So, I ended up with µGFX which is free and seems to have quite a lot of features.

My question is, is there anywhere a porting guide to bring µGFX to life on my Raspberry? Are there any functions like "SetPixel" and "GetPixel" to implement? Under GDISP/framebuffer there are some interesting files. Would it be sufficient to change the following functions?

gdisp_lld_init, gdisp_lld_draw_pixel, gdisp_lld_get_pixel_color

Is someone else interested in my project? Just send me a pm and I'll share the code with you.

+++

macload1

[inmarket]

Porting should be very easy.

Use the frame buffer driver. You only have to supply the board file. That file contains two functions. The first just needs to initialize the hardware and set the frame buffer pointer and size into a structure. The second function is optional and only needs code if the frame buffer needs a sync call.

There is a template in the frame buffer driver directory that you can copy and rename.

Any help you need just ask.

[macload1]

Hi inmarket,

You were right, porting is very easy.

I only had to write my own makefile, because James' one was really difficult to alter...

Then, on the first try, uGFX was written in blue on a black screen. Cool!

Only problem: my FreeRTOS tasks stopped working. I had two LED tasks running but when I launch "gfxInit();" somewhere in the code, then every task stop working...

Any hints on that problem? Are there maybe some examples out there for uGFX-FreeRTOS applications?

Many thanks in advance,

macload1

[macload1]

Okay,

when I disable the startup logo, everything works fine.

So, uGFX is up running on a Raspberry Pi with FreeRTOS operating system.

Greetings,

macload1

[Joel Bodenmann]

So, uGFX is up running on a Raspberry Pi with FreeRTOS operating system.

Glad to hear!

Could you please share your work with the rest of the world? This would help the project to become more popular as this is currently our biggest concern. The User Projects section of this forum is suited.

If you don't have a blog or something, I am more than happy to give you access to the new wiki so you can create a page there. I am planing to add a section in the wiki which shows many different demo projects anyway.

Let's see if we can find out what causes the problem with the startup logo and a halting FreeRTOS...

~ Tectu

[macload1]

Hi Tectu,

At macload1.frogcp.com you may find a short article of what I've done, a video and a download link for the source code.

When I have some time, I'll get into details.

If you want to create an article for that work, please, do not hesitate!

I'll try also to create a more sophisticated interface and post a video of that (you could maybe add this on your demo website).

Best regards,

macload1

[inmarket]

Thank-you for this fantastic work. It has been added to the repository.