SemiDrive E3 MCAL Configuration: ADC sampling uses DMA to transfer data.

1. Introduction

      SemiDrive provides MCAL that complies with the AUTOSAR standard, enabling drivers for hardware such as microcontrollers, storage, communication, and I/O. SemiDrive also offers AUTOSAR demo programs to showcase the invocation of these basic modules in predefined application scenarios. However, specific usage of certain modules is not explained in the demo programs. For example, the demo program for the ADC module uses the interrupt mode, but the usage of the DMA mode is not mentioned. This article aims to introduce the configuration and usage of the ADC's DMA mode, supplementing the usage methods of some modules.

2. Hardware and Software

      Hardware platform: SemiDrive E3640 SD103_E3_GATEWAY_A02_043 development board
      Software platform: SemiDrive_E3_MCAL_PTG3.0

3. DMA Overview

      The E3 series includes three DMA controllers: DMA_SF0, DMA_SF1, and DMA_AP. DMA_SF0 and DMA_SF1 each have 24 channels (16 channels for the E3206/E3205/E3106/E3104 series), while DMA_AP has 8 channels. DMA_SF0 and DMA_SF1 support Lockstep mode. DMA supports multicore and static channel configuration, and it automatically registers interrupts based on the channel information assigned to each core.
      Notes: The ADC supports data transfer via DMA. The ADC unit associated with the DMA group can only configure one group, and AdcStreamingNumSamples must be set to 1. Additionally, the DMA mode only supports software triggering.

4. Configuration Process

5. EB Configuration

1. ADC configuration is as follows:

2. DMA configuration:

       Allocate FIFO3 for DMA transfer

 

       3. ResM

       Assign DMA to the SF core

 

       4. After enabling the configuration through MCAL, the ADC cannot successfully initiate DMA transfer. Manual code addition is required.

 

       Normally, DMA transfer is integrated into the following function. By enabling DMA transfer through EB General and setting the ADC to DMA mode, DMA conversion can be initiated.

       Adc_StartGroupConversion(AdcConf_AdcGroup_Adc1Group_0);

       However, this function cannot directly achieve DMA transfer. It is recommended to add two lines of code to write to the registers for proper DMA transfer, as shown below:

 

       5. DMA configuration is as follows:

       6. ADC usage

       7. DMA transfer verification is as follows: