Re: [U-Boot] [linux-sunxi] Re: [PATCH] sunxi: set the default CPUx frequency of H5 to 816MHz

On Wed, Nov 1, 2017 at 7:40 AM, Ondřej Jirman megi@xff.cz wrote:

Hi,

Icenowy Zheng píše v St 01. 11. 2017 v 08:31 +0800:

...

And according to the Orange Pi PC2 and Prime schematics, they both start at 1.1V. (The Prime schematics even says "For H5 adjust VDD-CPUX to 1.1V).

Orange Pi PC2 starts at the same voltage as Orange Pi PC. That is at 1.308V.

It can be calculated from 0.6×(1+11.8÷10) as per the values of Ru1/Ru2 resistors in the schema. It is also my experience of working with these boards and writing the sy8106a driver.

I think you reverse the Ru values according to pc2 and prime schematic CPUX Vout = 0.6x(1+Ru1/Ru2)

so Ru1 10K and Ru2 11.8K then Vout = 0.6x(1+10/11.8) => 1.10V

thanks!