2020-05-20 01:58 AM
Hello,
The datasheet of STM32H753ZI specifies the maximum SPI clock frequency that the chip supports. For SPI4,5,6 in Master mode it is 50MHz in rev V and 100MHz in rev Y (tables 105 and 204) for highest power supplies.
However in the reference manual of STM32H7, the SPI4,5,6 maximum kernel clock is 125MHz. Which means a SPI clock frequency of 62MHz (prescaler of 2 minimum). So it is not possible to reach the 100MHz for rev Y.
What is the correct information ? Is it possible to reach 100MHz for rev Y ?
2020-05-20 04:13 AM
Hi,
50MHz / 100MHz belong to VOS1 in reference manual and datasheet. I don't find anything to VOS0 in datasheet.
Kind regards
Daniel
2020-05-20 05:35 AM
You're right ! It's pretty complicated just to find out the maximum possible frequency of a SPI... Do you know how to find the information in VOS0 ?
2020-05-20 06:25 AM
BTW why isn't there VOS3 in the Table 55: kernel clock ditribution overview of the reference manual (that gives the maximum kernel clocks for peripherals ?
2020-05-20 06:33 AM
I think this is a typo in revision 6 and 7 of the reference manual. VOS2 at right side is VOS3.
Did you mean table 59? If you don't mean 59 there is Rev7 available.
2020-05-20 06:37 AM
I hope the reference manual is correct.
To be honest i'm happy when SPI is working with 10-20MHz on my board.
2020-05-20 06:56 AM
****, of course it is a typo, sorry about that.
2020-05-21 05:25 AM
Hello,
Thanks for your feedback.
I recommend you to follow the revision V specifications.
Regards