AnsweredAssumed Answered

PPI in stop mode overshoots (BF537)

Question asked by carber on Jul 31, 2012
Latest reply on Sep 16, 2012 by carber

Hi, I'm trying to get my LCD to work with the PPI interface.

 

As a start I just want to fill the screen with the PPI in a one shot manner.

I use 2D dma in stop mode with the xcount as width and ycount as hight, and program ppi registers and timer registers accordingly.

 

When the dma is done I get an interrupt where I wait for the FS2 timer to finish and then disables dma, ppi and timers.

 

But it seems like the FS1 continues beyond the length programed in the count and frame registers so i get mor pixles written then I want to.

 

See the picture below, cursor T1 is where it should stop and T2 is where it actually stops.

ppi_one_shot.png

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