PSSI Performance Benchmarks

[TheMikeK]

Good morning everyone,

I am considering buying a PSSI-compatible STM32. Beforehand, I would like to get in touch with some users who have already tried the interface out. I am considering PSSI to stream data out over 16 parallel lines at around 50-100MHz, and I was wondering whether such continuous, uninterrupted streaming is feasible in terms of DMA throughput. 

Any experiences, remarks, and questions are highly appreciated.
Many thanks in advance.

Mike

[TheMikeK]

Note: My use case does not need any flow control, I simply want to clock out 16 bits of parallel data as fast as possible according to an external clock.

[Michal Dudka]

I've tested 8bit width 60MHz on STM32H7R3 (Fcpu=600MHz) from AHB-SRAM1 using GPDMA (transfered by 32bit words). The result was a completely smooth transmission without gaps. 

[Tesla DeLorean]

From my experience with other high bandwidth peripherals 60-62 MHz is going to be pretty close to the ceiling for these STM32 MCU devices, where you're getting data from one memory and pushing it at another. Plus whatever contention you might create in the process.

Sustaining it long term depends on if you're painting the same pattern or generating something on-the-fly.

SDRAM could be large, but is much slower than internal memories.

High speed external clocks, unlikely to be well synchronized with internal ones