Moving the needle in bare metal by using LTDC drivers.

[PM.5]

Hi...

I am working on stm32f746g board with display resolution of 480 x 272 . I have configured LTDC in 2 layers. One layer contains Gauge image & another with Needle image. Right now it is displaying static images of both gauge & needle. I want to move the needle. Does anyone knows how to move the needle by giving some values?

I want to know without using Touchgfx ,Embedded wizard kind of IDE's can we display a static as well as dynamic images like Gauge with needle rotating at user defined speed.

[KnarfB]

Image rotation by an arbitrary angle is not supported/accelerated in hardware. If the needle consist of few lines, polygons, ..., compute rotated coordinates and draw it from scratch each time the needle is moving. If the needle is a sophisticated pixel image, you need to implement image rotation yourself, probably with pixel interpolation, or, if the external flash size permits, pre-compute 100 or so rotated needle images and store them in flash.

hth

KnarfB

[PM.5]

Thank you for the reply.

I tried by Touchgfx IDE .It is working fine when FREERTOS has enabled. But when the same thing I try to do by disabling FREERTOS it is not working. What is the issue I am not getting. As I was unable to display without FREERTOS, I tried just by using two LTDC layer, now I got to know it will be little complicated when I go higher level.

The files configured with RTOS & without RTOS I have given below . Please go through those if possible & if any suggestion please let me know .

Pooja M

[MM..1]

Your zip seems as project from TouchGFX ... designed and optimized for RTOS.

For noOS you need create project from scratch and no edit some parts...

[PM.5]

Thank you for the reply.

Your second point is not clear , what do you mean by creating from scratch & no edit some part . Can you please explain it.

I tried to do as per this link , but Its not working.

https://community.st.com/s/question/0D53W00000HNRWBSA5/how-to-run-touchgfx-without-rtos

Pooja M

[MM..1]

As in article is writed “ in CubeMX (and regenerate code) “,
but Alexandre omit say : TGFX created projects isnt perfectly prepared for this. Regenerating from ioc corrupt some custom setups.
And primary i explain regenerating only swap generated files. If other files exist, stay as is for first generation config.
For example in target folder files stay and in target/generated is reconfigured for noOS or for other colour or any other change.
MX wizard isnt miracle for one click and LCD works. Debug your code and ...