SPI Communication with DMA transfer

[BRémy.1]

Hello,

i'm working with the STM32F746G-DISCO development kit. I need to use 3 SPI in reiceive only master mode (each SPI have the same clock). The data comming from the SPI are clocked at 4[MHz]. I need to use DMA to transfer data from the SPI peripheral to the memory.

The fact is this data are measurements and i need these measurements are synchrounous. When starting and stoping the SPI that take some time and the data are no longer synchronized. I don't know how i can synchornize this measurement, have you an idea ?

[berendi]

What has to be synchronized to what? The SPI masters to each other?

[BRémy.1]

The 3 SPI master must save data in the same time. This is needed because i use the SPI data to do some calcul. More precisely I need the signal phase in my calcul. You will therefore understand that if the SPI data are not take in the same time, the phase will be wrong.

[S.Ma]

Hmm.. how about configure 1 SPI as Master (use dual lane even if MISO is not going to a pin), and the other 2 as Slave (receiving the master clock)

This way, you can set 3 DMAs filling each one its buffer with the clock generation from a single SPI to manage.

Would this decomplexify the handling?