STM32F103 - DAC

[jaykov]

Posted on August 02, 2015 at 14:00

Hi dear friends,

I have the SMT32F103RCT6 and I trying to use the DAC with DMA. I compile the ''OneChannelDMA_Escalator'' example and unfortunately it won't work, When I change the code so it will work without the DMA i can see the signal in my scope.

I attach the code that i using,Regards, Yakov S. #dac #gpio #dma #stm32f103

[raptorhal2]

Posted on August 02, 2015 at 15:34

Your code is not a faith full copy of the library example. The DAC tigger timer needs to be enabled after the DAC is configured.

Cheers, Hal

[jaykov]

Posted on August 02, 2015 at 16:02

Dear Hal,

I edit the code so i can compare it with my other ST code that work. All the other examples and the original file is not working. I guess that is set wrong configuration to the DMA. I tried your suggestion and enabled the timer after the DMA and DAC configuration, Still it won't work.Regards, Yakov S.

[raptorhal2]

Posted on August 02, 2015 at 17:04

The only other problem I see at the moment is filling the DAC right aligned register with left aligned data.

Other priorities prevail at the moment. I will have a look at this later. Cheers, Hal

[raptorhal2]

Posted on August 02, 2015 at 22:23

I believe the  DAC_DHR12R1_ADDRESS   should be 0x40007408.

Cheers, Hal

[jaykov]

Posted on August 03, 2015 at 14:48 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=0680X000006I6i4&d=%2Fa%2F0X0000000btj%2FIirauUjdjBK1mMNr0x6hgpJ9DGM991vcpOUsD4yXRDM&asPdf=false

[raptorhal2]

Posted on August 03, 2015 at 15:22

A brief tutorial seems to be needed here.

Each DAC has a data holding register for each allowed input data alignment of 12 bit left or right and 8 bit. See Section 12.5 in the reference manual. Each register has it's address offset from the peripheral's base address. The library example is for 8 bit data, but you used the address for the 12 bit right aligned register. The library example has defines for low density (LD) and medium density (MD) devices and a default for all others. I believe you have a high density (HD) device. Check your defines and make sure the selected code applies to your device. Cheers, Hal

[jaykov]

Posted on August 03, 2015 at 16:55 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=0680X000006I6i9&d=%2Fa%2F0X0000000btk%2FJJpj2Tqd7tfm6.0Bz9iGKfxNTdWa7vDLnWSQm1xbGYE&asPdf=false

[raptorhal2]

Posted on August 03, 2015 at 18:15

Did the previous 8 bit data code work with the correct register address ?

Cheers, Hal

[jaykov]

Posted on August 04, 2015 at 08:38

Dear Hal,

It work fine without the DMA the address that I use is 0x40007410 for 8 bit data.When I use the DMA with the same address (I check all kind of address non of them work) it won't work, I can't see on my scope the waveform.It's seem to me that the problem is in the DMA or the timer.Regards, Yakov S.