How to configure the DMA in ADC and how to use ASYNC API in ADC

[jyoti yadav]

How to configure the DMA in ADC and how to use ASYNC API in ADC .please provide any sample example code for ASYNC ADC and ADC DMA

[haakonsh]

What SDK are you using, nRF5_SDK or nRF Connect SDK?

DMA is always enabled for the SAADC peripheral. 

[jyoti yadav]

DMA is always enabled for the SAADC peripheral. Where i can get the DMA related driver code in which file ?I want to understand the flow of the code where the DMA is enabled . Do we need to add extra config for Enabling DMA?

[haakonsh]

You can find the example at https://github.com/haakonsh/NCS_SAADC_example/tree/master. 

[jyoti yadav]

Hi,

No not about the sample, i just need to understand where in SAADC driver code, is DMA enabled..?

As, I cannot see DMA related code anywhere in SAADC driver code,

Kindly point me to the same

[haakonsh]

DMA is always enabled, the SAADC cannot operate in any other way. 

[szhaulai]

Hi, this is the exact example I wanted for nrf5340. I tried to run your example. But get a list of errors related to PPI packages. I am using ncs1.8. Should I change those ppi to dppi in nrfx_ppi.h ? Please help!

In file included from C:\Users\info\ncs\v1.8.0\modules\hal\nordic\nrfx\drivers\include\nrfx_ppi.h:38,
                 from c:\Users\info\ncs\firmware_v3\NCS_SAADC_example-master\src\main.c:10:
C:\Users\info\ncs\v1.8.0\modules\hal\nordic\nrfx\hal\nrf_ppi.h:54:25: error: 'PPI_CHEN_CH0_Pos' undeclared here (not in a function); did you mean 'DPPIC_CHEN_CH0_Pos'?
   54 |     NRF_PPI_CHANNEL0  = PPI_CHEN_CH0_Pos,  /**< Channel 0. */
      |                         ^~~~~~~~~~~~~~~~
      |                         DPPIC_CHEN_CH0_Pos
C:\Users\info\ncs\v1.8.0\modules\hal\nordic\nrfx\hal\nrf_ppi.h:58:25: error: 'PPI_CHEN_CH4_Pos' undeclared here (not in a function); did you mean 'DPPIC_CHEN_CH4_Pos'?
   58 |     NRF_PPI_CHANNEL4  = PPI_CHEN_CH4_Pos,  /**< Channel 4. */
      |                         ^~~~~~~~~~~~~~~~
      |                         DPPIC_CHEN_CH4_Pos

[haakonsh]

You need to open up a new ticket on this subject.