2021-01-27 08:09 AM
We use TouchGfx with a STM32f769 on a custom board. There are many ui widgets like textarea, boxes and buttons. At first the display had a flicker problem. That was solved with just invalidating widgets that should update.
Now the problem is that if a single widget updated with .invaldate(), an other widget - which was previously invalidated - is suddenly flickering.
I found that this occurs with double buffering activated.
Any ideas that could help?
Thanks in advance.
2021-01-27 08:31 AM
Hi,
Maybe you are reaching the maximum bandwidth of your SDRAM.
What is your screen size, bit per pixel, and SDRAM width (8, 16 or 32bits)?
2021-01-27 11:38 AM
How version TouchGFX you use, and generated code is from CubeMX?
2021-01-28 12:11 AM
The fact that this happens only with double buffering makes your statement my first guess as well. @MVils.1 Have a look at your mapfile (.map) and check your memory usage.
/Romain
2021-01-28 12:55 AM
@Community member
800 x 480 x 16 bpp and SDRAM width is 32bits. LTDC clock 27.375 MHz.
@Romain DIELEMAN
Memory usage looks good. I don't know how to check sdram memory usage, but it's a 128 M and this should be enough ..
2021-01-28 01:06 AM
I tought that TouchGfx is always at latest version in cubemx because i check updates often. Just now i saw that you have to migrate the TouchGfx version for your project too. Thanks for the hint.
2021-01-28 03:55 AM
With your config, you shouldn't hit the SDRAM max bandwidth.
Maybe check that your FMC is set to run at 100MHz.
2021-01-28 06:41 AM
You dont reply numbers , but you can check my example BUGREPORT TouchGFX 4.16 strange display
2021-02-01 02:21 AM
Old version was 4.15. Now i migrated to 4.16. I had a strange memory access problem after the update. Could only solve it with a complete regeneration of the cube ide project. But sadly the trouble with flickering widgehts still persists.
2021-02-02 12:14 AM
FMC is set to 108 MHz. I read that max is 100 MHz but lowering that didn't help.