TouchGFX with custom Display

[DPfei.16]

Hello,

when I run the code with the STM32F769 discovery bord display, everything works fine.

But when I use a differnt display the constructor for the start screen is not called from touch gfx lib.

Does anybody know why this is only working with the discovery display?

BR

Daniel Pfeil

[Martin KJELDSEN]

Hi @DPfei.16​,

TouchGFX is display-agnostic. You can use any display you like, as long as the hardware init is correct, the method of transferring the framebuffer being rendered into (by TouchGFX) is correct and the syncronization between display and TouchGFX is set up.

What could be wrong is that you're not handling the sync from your display properly and calling OSWrappers:signalVsync() - The HAL main event loop is waiting for this signal in order to proceed with rendering. What have you done in code to prepare for this display?

/Martin

[DPfei.16]

Hi Martin,

OK, thank you for the info.

Now I call the OSWrappers:signalVsync() function from the LTDC line interrupt when the active area is entered.

With this change the start screen constructor is called now and the start screen is printed to the display.

But after that I get a Hardfault.

The display is running in DSI video mode.

Do you have any idea?

BR

Daniel

[DPfei.16]

Hi Martin,

in CubeMx there is the following problem:

1) DSIHOST: Select "Video Mode"

2) GRAPHICS: For the "Display Interface" the fild "Display Serial Interface using LTDC-DSIHOST" can not be selected.

Do you have any idea?

BR

Daniel Pfeil

[DPfei.16]

May you call me on Monday?

[phone]

[Martin KJELDSEN]

Hi @DPfei.16​,

Can i see your HAL implementation? Are you using one of the existing ones we have for parallel RGB / DSI? Thing is, we do not have anything running in DSI Video mode, so there may be something here. The _DSI.cpp files we distribute with our Application templates are all based on command mode. For video mode you could try simply using a parallel RGB version and signaling TouchGFX VSYNC on the TE signal intsead. If you need help with that let me know.

/Martin