Part Number: MSPM0G3519
Hi Team,
We are using the MSPM0G3519 MCU in our system with a total of 14 ADC channels configured as follows:
ADC12_0: 7 channels
ADC12_1: 7 channels
Currently, ADC values are read every 500 ms using the ADC_GetRawValue(x, y) API. This implementation works correctly, and all channel values are read as expected.
To reduce CPU overhead, we are trying to use DMA to transfer the ADC conversion results directly into RAM. However, the transferred data is not reliable. Some channels occasionally contain 0, even for inputs that are constant (for example, a fixed input voltage), where a zero value is not expected.
Current DMA configuration is:
DMA sample count: 7
DMA trigger: MEM6 result loaded interrupt
Address mode: Fixed Address → Block Address
Automatic enable: Disabled
Source length: Half Word (16-bit)
Destination length: Half Word (16-bit)
Transfer size: 7
Transfer mode: Repeat Block
Settings: Settings.txt
Recorded ADC data: DMA_Buffer.csv
Init,
/* ------------ ADC0 DMA ---------------- */
DL_DMA_setSrcAddr(DMA, DMA_CH0_CHAN_ID, DL_ADC12_getFIFOAddress(ADC12_0_INST));
DL_DMA_setDestAddr(DMA, DMA_CH0_CHAN_ID, (uint32_t)adc0_dma_buffer);
DL_DMA_enableChannel(DMA, DMA_CH0_CHAN_ID);
/* ------------ ADC1 DMA ---------------- */
DL_DMA_setSrcAddr(DMA, DMA_CH1_CHAN_ID, DL_ADC12_getFIFOAddress(ADC12_1_INST));
DL_DMA_setDestAddr(DMA, DMA_CH1_CHAN_ID, (uint32_t)adc1_dma_buffer);
DL_DMA_enableChannel(DMA, DMA_CH1_CHAN_ID);
Our expectation is that, after a 7-channel conversion sequence completes, DMA transfers the seven 16-bit ADC results into a RAM buffer.
We would like to clarify the following:
- Does the MSPM0G3519 ADC support DMA transfers for a 7-channel conversion sequence directly into RAM?
- If so, what is the recommended DMA configuration for this use case?
- Is MEM6 result loaded the correct DMA trigger, or should a different ADC event be used?
- Are there any additional ADC or DMA settings required to reliably transfer a repeated multi-channel conversion sequence?
Thanks & Regards,
Earnest Abraham