How to configure MDMA memory-to-peripheral (16 parallel bus) transfer rate using a clock?

[BBeha]

Hi,

I want to send a sequence of data on a 16 GPIO bus with a linked-node MDMA setup. How do I set the transfer frequency? I have set up LPTIM1 to have the required clock, but I can't find a way to force the MDMA to have this clock control the output

Thanks!

[Tesla DeLorean]

Which part specifically?

Usually RM shows DMA channel association with trigger sources.​

[BBeha]

Not sure what you refer to (RM ?)

my problem is that if I ask MDMA for a transfer - I cannot control the speed - either of one burst, or between blocks, or between transfers. I want every half-word to have 100ns (10 MHz) for example

[waclawek.jan]

> Not sure what you refer to (RM ?)

Reference Manual for your particular mcu family. You did not tell us which one do you use.

Assuming you are using STM32H7x3, in RM0433, tables in chapter Block interconnect, subchapter DMA list the triggers available for individual DMAs. MDMA there has no connectivity with any timer, so you can't control MDMA using a timer. Resort to other DMA which can be triggered by a timer. Note, that DMAs in 'H7 other than MDMA use one of the DMAMUX modules to steer triggers.

JW

[BBeha]

Thanks.

Yes stm32h743 in nucleo board.

Thanks.