TouchGFX idling on a screen sometime is showing random lines

[SLiau]

Hi, I'm Hill-Rom employee and working on UI software. On the device LCD screen if leaving a screen idle for a while, sometime will observe some random lines showing on screen.

Not every time idling on the same screen can reproduce the issue but when the problem comes it's always the same lines appearing on the screen. Can you help me find out the problem?​

[Martin KJELDSEN]

Hi @SLiau​,

That sounds a bit tricky to debug. Can you show me a screenshot to begin with?

Thanks.

[Martin KJELDSEN · Accepted solution]

Could be some sort of memory contention. You have the LTDC and DMA2D accessing SDRAM at the same time, and maybe something else too?

Are you still having this problem?

/Martin

[SLiau]

Hi Martin,
Sorry for the very late reply. Big thanks for pointing out LTDC and DMA2D accessing SDRAM at the same time.
I’ve tried adding Interrupt Critical region to both interrupt handler (LTDC & DMA2D), ISR_CRITICAL_ENTER() and the random line issue no longer happen. I believe it helps to prevent LTDC & DMA2D accessing SDRAM simultaneously.
In this case, I did no lockDMAToFrontPorch and maintain good performance.
Thanks again.
Shu Hwa

[Martin KJELDSEN]

Hi Shu Wa,

That's great to hear!

Best regards,

Martin