RE: The Spec. Sheets for Privileged and Unprivileged...

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Mala Dies

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Jan 24, 2021, 1:41:50 AMJan 24
to BeagleV
Hello,

I have been reading the unprivileged specification sheet. Is this RISC-V spec. sheet for unprivileged use a warning of what not to do?

Seth

P.S. I am on Chapter Two and working through it slowly. I will get to the shorter, privileged spec. sheet soon. If anyone here knows of what I am describing, please share, yell, or empower my mood towards the BeagleV.

Drew Fustini

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Jan 24, 2021, 2:07:13 AMJan 24
to Mala Dies, BeagleV
The SiFive U74 cores in the StarFive SoC implement RV64GC. The core
also implements the privileged spec which allows it to run a full OS
like Linux where there is a distinction between M-mode (machine mode)
and S-mode (supervisor mode). I recommend checking out this talk
about SBI: https://www.youtube.com/watch?v=jstwB-o9ll0 SBI is the
interface between the bare-metal mode and the OS kernel.

Also, while the specifications can be useful to read, I highly
recommend the RISC-V Reader:
http://riscvbook.com/

There is a PDF available here:
https://github.com/Lingrui98/RISC-V-book/blob/master/rvbook.pdf

-drew

Mala Dies

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Jan 24, 2021, 2:49:22 AMJan 24
to BeagleV
Hello...thank you. I appreciate your quick reply. I will look over the links to better associate BeagleV w/ RISC-V specs. and the SBI. 

I am glad you all are paying attention to new set up chips for your open source platforms.

Seth

P.S. Although I may never use one in real time w/ machinery or machine learning or AI (etc), my hobby has brought me this far. I plan on keeping it. If I am not picked to test the hardware/software, I will stay patient for the community testing board to populate the national stores. I basically started when the BBB 2GB versions came out. I was a couple years late on in that respect. "There is always catch up work to perform."

Mala Dies

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Feb 5, 2021, 7:37:41 PMFeb 5
to BeagleV
Hello,

I just got my hands on the RiscVBook. Thank you. 

Seth

P.S. There is nothing like advancing before the actual release date. Oh and I found on the #beagle channel on Freenode that there is a U74 chip on the board you all are producing w/ StarFive and Seeed and it has a datasheet. phew...here it is: SiFive U74 Manual: 20G1.03.00 (prismic.io) .

Anyway, the more I read and the more I configure things, the more support I can provide to this BeagleV support. So, w/out further ado, off to look up the other resources and peripherals on the board.

On Sunday, January 24, 2021 at 1:07:13 AM UTC-6 drew wrote:

Mala Dies

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Feb 5, 2021, 7:47:14 PMFeb 5
to BeagleV
Hello,

If you are into cameras and tech, I found a neat short on specific CSI-2 tech. here online: https://www.vision-systems.com/boards-software/article/14173598/mipi-csi-2-interfaces-for-embedded-vision-systems .

It seems there are many, different cameras one can purchase to handle this tech. "The more, the merrier!"

Seth

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