Skip to main content
Michael Schmid
Michael Schmid
Associate II
February 19, 2020
Solved

parallel synchronous slave interface (PSSI) Host-to-Host app-note or example.

  • February 19, 2020
  • 5 replies
  • 5620 views

Dear all,

ST brought a new feature to the STM32H7A/B and some L4+ MCUs, the "parallel synchronous slave interface (PSSI)". We would like to use this for a fast host-to-host communication. But this interface seem so new, we could only find register description in the RM0432 Reference manual. Are there any code example or app-notes for PSSI host-to-host communication?

Thanks.

This topic has been closed for replies.
Best answer by Amel NASRI

Hi @Michael Schmid​ ,

To answer your question: I assume this was just the example choice as PSSI can be configured in both 8-bit or 16-bit parallel data input or output.

Then, it may also be related to hardware constraint: we don't have all required pins available in both boards for 16-bit mode.

For my curiosity: could you please explain how will you be using this interface as a host-to-host while PSSI is operating in slave mode? Which device will be connected in your case? For the example, we used 2 NUCLEO-H7A3ZI-Q.

-Amel

5 replies

Michael Schmid
Michael SchmidAuthor
Associate II
February 20, 2020

To answer my own question: I have found a great example under

https://github.com/STMicroelectronics/STM32CubeH7/tree/master/Projects/NUCLEO-H7A3ZI-Q/Examples/PSSI/PSSI_Transmit_Receive_DMA

The only question open now for me: In the above example, only 8 bit data width is used. What changes would be required to use a 16 bit wide bus? Is there a reason, why only 8 bit, out of the available 16 bit, was used?

Amel NASRI
Amel NASRIBest answer
ST Technical Moderator
February 28, 2020

Hi @Michael Schmid​ ,

To answer your question: I assume this was just the example choice as PSSI can be configured in both 8-bit or 16-bit parallel data input or output.

Then, it may also be related to hardware constraint: we don't have all required pins available in both boards for 16-bit mode.

For my curiosity: could you please explain how will you be using this interface as a host-to-host while PSSI is operating in slave mode? Which device will be connected in your case? For the example, we used 2 NUCLEO-H7A3ZI-Q.

-Amel

To give better visibility on the answered topics, please click on "Best Answer" on the reply which solved your issue or answered your question.
Michael Schmid
Michael SchmidAuthor
Associate II
March 1, 2020

Dear Amel,

To answer your question: when I was writing host-to-host, I was thinking about the function of the chip, not the interface mode. Of course, there will be a master and slaves, as in the example with the 2 NUCLEO-H7A3ZI-Q boards.

About the pin constraint: When I use STM32cubeMX, select the NUCLEO-H7A3ZI-Q board, initialize the default periphery, I can select PSSI with 16 bit wide bus. Could you tell me, what pins are missing for a 16 bit wide implementation?

Thanks.

LGonz.1
LGonz.1
Visitor II
May 9, 2023

Dear community,

do you have the example working as you expected? Recently I try it but the master stuck as no one package were received. With polling and generating pulses with a gpio I accomplish to receive data but it required to have two adittional clocks before DE get low and one or two pulses after. Another observation is that after transmitting a package the clock polarity change from FALLING to RISING. is the any errata?

Terms & ConditionsAccessibility statement