STMU575VGT6 SPI3 TransmitReceive problem in LPBAM

[Sajjadonbussiness]

Hi everyone,

I want to read data from an SPI slave using SPI3 while the MCU is in STOP2 mode.

The communication protocol requires me to transmit a command before receiving the response.

I configured LPBAM according to the following YouTube tutorial, and my CubeMX/LPBAM configuration is shown in the attached screenshots.

My observations are:

• If I use only the “Transmit Data” node, everything works correctly.
• If I add a “Receive Data” node after the transmit node, the SPI transaction stops when it reaches the receive node. However, the “LPTIM1_CH1” output continues to generate trigger signals.
• If I replace them with a single “Transmit Receive Data” node, neither SPI nor LPTIM1_CH1 works.

Could you please explain what might be causing this behavior? Is there any additional configuration required to use the “Transmit Receive Data” node in LPBAM with SPI3 in STOP2 mode?

Thank you.

 

[Saket_Om]

Hello ​@Sajjadonbussiness 

Please refer to the example below which show How to handle SPI two consecutive communications (full duplex then simplex) between two boards with DMA linked-list feature in low power mode through LPBAM utility.

STM32CubeU5/Projects/NUCLEO-U575ZI-Q/Applications/LPBAM/LPBAM_SPI_TransmitReceive at main · STMicroelectronics/STM32CubeU5