2024-03-07 05:00 PM
Hi I m using SPI DMA on H7 series, and notice under SPIx_TX and SPIx_RX there are at least 14 DMA channels to choose from, i.e DMA1 Stream 0-7 and DMA2 0-7. Can i select these "channel" randomly or is there a reference manual that state otherwise? Likewise i saw the same case in USART DMA too, anyone can advise?
2024-03-07 09:00 PM
Older STM32 have a fixed connection from peripherals to individual DMA Channel/Stream. 'H7 does have DMAMUX though, read DMAMUX chapter in RM.
JW
2024-03-07 09:36 PM
ok, which RM document to check DMAMUX? i m looking at 750 reference manual but its not stated there...kindly advise thx.
2024-03-07 10:28 PM
For H723 - H735 it's chapter 17 in the reference manual (RM), directly after DMA chapters.
You can (almost) freely assign the DMA streams ( = channels), just check that the DMA can access the memory area (here: chapter 2: Memory and bus architecture ).
And mind that the lower channel number, the higher the priority in case of equal prio register setting.
2024-03-08 12:21 AM
Hello,
There is also the AN5224 "STM32 DMAMUX: the DMA request router".