Choose Interrupt or DMA for UART and SPI slave for minimum cell energy consumption

[David_]

Would Interrupt or DMA consume less cell energy (need months of cell life)

for UART and SPI for STM32WLE5JCI6?

SPI links with slave sensor chip. Data volume 100 bytes per second.

STM32 master SPI clock can choose 2 to 10 MHz as slave sensor specification.

MCU stays in power saving mode for most time.  Only wake up briefly to do simple processing and back to power saving mode ASAP.

Use Sequencer in utility of HAL WL firmware library

For these HAL library functions.

(+) HAL_UART_Transmit_IT()

(+) HAL_UART_Receive_IT()

(+) HAL_UART_Transmit_DMA()

(+) HAL_UART_Receive_DMA()

HAL_SPI_Transmit_IT()

HAL_SPI_Transmit_DMA()

HAL_SPI_Receive_IT()

HAL_SPI_Receive_DMA()

Many thanks

[STTwo-32]

Hello @David_ 

If you are looking for an Ultra-low-power application on the STM32WL, i suggest you to take a look at the AN5568. For your specific questions, i suggest you to test each implementation and measure the crurent consumption to assume the best implementation.

Best Regards.

STTwo-32