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STM32F7 Discovery Board ADC+DMA Problem

ferhatyol-23
Senior
Posted on December 30, 2015 at 09:56

 

 

The original post was too long to process during our migration. Please click on the attachment to read the original post.
8 REPLIES 8
ferhatyol-23
Senior
Posted on January 05, 2016 at 22:25

Is there anyone who can help?

The cause of the problem is DMA2 module. ADC3+DMA2 is not running while LCD+SDRAM running. 

SDRAM used DMA2 Channel 0 and Stream 0

ADC3 used DMA2 Channel 2 and Stream 0

ADC and SDRAM using different channels. But it does not work simultaneously.

What could be the problem?

Thanks

but it

does not work

simultaneously.

Posted on January 06, 2016 at 01:25

Is there anyone who can help?

There doesn't seem to be... Forums can be like talking into an empty room.

If it's like the F4 DMA implementation you need to use unique streams, not channels.

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ferhatyol-23
Senior
Posted on January 08, 2016 at 09:17

hi clive

So what can be done about it? Do you have a suggestion? I could not run the ADC3 with the DMA. 

Thanks for the reply.

Posted on January 08, 2016 at 13:31

So what can be done about it?

I don't know, use *different* Streams? My guess is your SDRAM one is Memory-to-Memory, can't you pick some arbitrary Stream for that? The ADC3 can use Stream 0 or Stream 1. Remember the CHANNEL is a knob to select a trigger source, the STREAM is a physical controller, and DMA2 has EIGHT of them each handling a unique source.

0690X00000605ZPQAY.png 

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ferhatyol-23
Senior
Posted on January 08, 2016 at 23:43

hi clive

Thank you for the reply

Yes, I looked at the table. ADC3 only works with Stream 0 or Stream1. I tried them all. But I can not run.

Do you want to examine the my project.?

Posted on January 09, 2016 at 01:29

Not really, the HAL/F7 is stuff is outside my area of interest/expertise, perhaps some of the ST staff or FAE's can step up and support their products.

Does the ADC work if you don't use the LCD?

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ferhatyol-23
Senior
Posted on January 09, 2016 at 10:35

The original post was too long to process during our migration. Please click on the provided URL to read the original post. https://st--c.eu10.content.force.com/sfc/dist/version/download/?oid=00Db0000000YtG6&ids=0680X000006I6pP&d=%2Fa%2F0X0000000bwJ%2FnoOiWH66Clhfsr2BukwJVYv_XISz4.H2SilhRUbFbRg&asPdf=false
Mary Solomo
Associate II
Posted on March 22, 2018 at 06:05

I had similar problem on STM32F429 and the solution is to change the ADC DMA stream to other than stream 0. LCD is using DMA stream 0 that's why LCD and ADC-DMA wasn't working before.