2024-09-25 10:21 AM
Hi,
as the question indicates, I wonder what the max (rated?) speed on SPI is if the Nucleo board is connected to a carrier board (with very short leads with proper SI) to a SPI master/slave device. I searched for information on the ST Zio connector connector but found no rating or expected max frequency, nor experimental results.
Thanks in advance!
/Mike
2024-09-25 12:07 PM
Hi,
so - just try it yourself.
From my SPI use : on longer connections, with "good" adjusted pin speed, 16Mbit is no problem.
(At 32M the receiver (TFT) got errors, so cannot say about the H7 any limit ; H7 can run 100Mbit. )
On higher speeds - most time its over the limits for the receiving chip.
And try pin speed as low as possible to reduce reflections. Just try...or look with a fast scope, but this is not easy, if you have no experience with it.
2024-09-25 12:14 PM
I doubt there's that level of contractual commitment.
Going to depend a lot on the specific signals and traces, and if there are stubs or other things attached.
I'd expect at least 25-33 MHz with low/minimal effort/attention.
Perhaps 33-50 MHz with some attention. And 50-66 MHz with specific attention to detail.
You can also scale back the pin drive / slew rate to reduce the energy imparted into the lines.
H7 also want to enable IO compensation.
2024-09-25 01:37 PM
Depends mostly on your layout. I was able relatively easy to establish 50MHz communication through "Zio connector".