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Problems with BDMA (from memory to peripheral)

JGon?
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I need to do a project where I use the BDMA to transfer arrays from memory to the GPIO. The idea is to send the information in 8 bit parallel at 12.5MHz.

I started with the DMA example from the STM32 (called DMAMUX_RequestGen) to try to understand how the BDMA works.

I started with this array.

0690X0000088TNRQA2.png

In the example, the BDMA is set to transfer two bytes in circular mode using this function 0690X0000088TKcQAM.png

In this case the program runs correctly and I get a signal like this (the idea is to get a square wave):

0690X0000088TLLQA2.jpg

But when I change the function so it sends 8 values in circular mode,

0690X0000088TLpQAM.png

the signal gets "corrupted" (I was expecting the signal to be like the one in the last capture):

0690X0000088TM9QAM.jpg

I need this signal to not be "corrupted" with more than 4 elements because I need to send more than 240 bytes in a row.

I tried to see were the problem is but I am not having any luck.

Has anyone got any idea?

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