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SLiau
Associate
Mar 22, 2019 7:55 AM UTC
Solved

TouchGFX idling on a screen sometime is showing random lines

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?​

This topic has been closed for replies.
Martin KJELDSEN
Martin KJELDSENBest answer
Principal III
Apr 3, 2019 8:50 AM UTC

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

4 replies

Martin KJELDSEN
Principal III
Mar 22, 2019 12:53 PM UTC

Hi @SLiau​,

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

Thanks.

Martin KJELDSEN
Martin KJELDSENBest answer
Principal III
Apr 3, 2019 8:50 AM UTC

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
SLiauAuthor
Associate
Apr 30, 2019 6:11 AM UTC
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