STM32H750VB Quad-SPI questions

Yevpator · ‎2019-03-22

Hello,

Due to so attractive price + some specific features, the H7 Value Line looks to me very attractive to take into a new design, but 128kB Flash is not enough for me, I have to take an external flash, which is QSPI. I have a few basic questions about that.

1. I am almost sure that Quad-SPI works with the Value line H7 as well, but since I saw in some doc that an H7 Discovery works with Dual SPI only, I have some hesitation. Can one here confirm that?

2. If work through Quad-SPI (QSPI Memory Mapped), how the performance will be reduced vs a normal mode @ 400MHz?

3. Does this Quad-SPI make debugging more complicated? What issues did you face , especially with Atollic?

4. Does ST-Link support H7 programming with Quad-SPI enabled?

5. What are other issues with H7 + Quad SPI, you would recommend me to take in account ?

Thanks!

Yevpator · ‎2019-03-31

Thank you Andreas for the answer.

"If the benchmark spends most of the time in tight loops, cache is enabled, "

I don't think the real life code looks like you described above.

Anyways, there is 1MB RAM and I don't think I need more than let's say 50K, so do you agree that running from internal SRAM is a better alternative than XIP, 2 X QPI, because :

it is always faster, as it does not depend if the code "spends most of the time in tight loops"
It is cheaper - I can use 1 NOR flash, even not necessary Dual, Quad SPI or QPI vs 2 QPI chips as you suggested

Your help is very valuable, appreciate that!