Attempting to run OctoSPI on STM32H753ZI

[sammie.k]

It might as well be a dumb question, but is it in any way possible to connect and communicate with a Octo SPI slave with the dual Quad-SPI interface available on the STM32H753ZI?

Thanks and best!
Sam.

[raptorhal2]

Presumably, yes. For more definitive answers, identify the slave device.

Compare H743 Dual or Quad SPI pin compatibility with the slave.

[sammie.k]

Thanks, that sounds promising, then! We intend to connect the memory module APS512XXN-OBRx to the STM32H7x3, and (almost) all the pins (except 1) are compatible to the dual Quad SPI. The only concern remains is with the DQS/DM (/RWDS - R/W data strobe), which does not exist on the quad SPI. I might give a try to achieve this using another pin, but would be glad to get other ideas to implement the same.

Best!
Sam.

[LCE]

I recommend to test this before doing a PCB layout. QSPI seems a little restricted on some STM32.

And ask AP Memory, they have a really nice and helpful guy called Alex around here: @Alex - APMemory 

[raptorhal2]

Check the APS data sheet timing diagram. I suspect RWDS is just another name for the SPI clock.

[Tesla DeLorean · Accepted solution]

Uphill both ways..

Good time to revisit part choices, the H743/753 is VERY OLD, surely better choices, and perhaps pin compatible/similar parts with better designed and tested options.

[raptorhal2]

My correction, RWDS is not the SPI clock.

The STM32L5 has OCTOSPI with DQS. Take a look.

[sammie.k]

We are still in the contemplation phase, so we do have time before we decide on the PCB design. But yes, our estimates at going for Octo SPI using QSPI seem to be overhelming.

[sammie.k]

The speed of STM32L5 is slow for our necessities. We are now looking at STM32H735, which seems to fulfil our requirements almost as (maybe better than!) the STM32H753. I shall keep you guys posted. Thank you!

[LCE]

The H735 is definitely working great with OCTOSPI in HyperRam mode, I have that right beside me on the table, using the H735 Discovery Kit, you should check its schematics.