Homebrew computer using RISC-V CPU?

Archive RISC-V
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Hello guys, I’m new and I’ve been keeping track of RISC-V since I heard of it last year or the year before. Now as far I as I can tell SiFive is the only company that has RISC-V hardware available for sell, and I’m wondering when the U54-MC CPUs will be available.

At this stage is it possible to build a Homebrew personal computer around RISC-V hardware. The free and open nature of RISC-V highly appeals to me as I’m a Linux user who no longer even uses Windows anymore.

Thanks for any answers .

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SiFive have said 1st quarter 2018 for the U54-MC. With 1.5 GHz quad core that will be quite a usable PC. Hopefully it will be closer to an Odroid C2 than to a Raspberry Pi in performance.

For the moment if you want to run a real OS then you’re limited to a soft core in an FPGA and maybe 100 MHz. I’m old enough to remember when I’d have thought that was a pretty good PC, but it would be a bit painful running a web browser these days. It’s also going to cost a lot more than an ARM or x86 based machine.

The question of GPU also hasn’t been addressed. Those are fairly vital to the experienced performance of PCs these days.

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Thanks, I was wondering about what GPUs were being looked at. Are there any free and open GPUs in development even on “paper”? If U54-MC boards are available with PCIe x16 slots I supposed we could use AMD Radon Rx 550 GPUs and higher since they have FOSS drivers available to examine.

BTW I’ve been building my own x86 computers since late 2000.

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What do you define as “building”?

With all my x86 desktops since whenever the Athlon “Thunderbird” came out, which was … yeah … 2000, I’ve “build” them myself, defined as: pick a CPU, ATX motherboard with the same socket, RAM to fit the MB, disk with appropriate IDE/SATA/M.2 interface to suit the motherboard, case, power supply … and plugged it all together. A process taking an hour maybe.

In 1983 two friends and I built a 6809 computer by buying a 6809, some RAM chips, a ROM chip, some TTL logic chips, and we figured out which pins to connect to which pins and we wire-wrapped the whole thing. I was particularly proud of the clock circuit I designed which ran at 1 MHz while accessing the UART, at 2 MHz while accessing the RAM, and at 1,33 MHz (500 ns high, 250 ns low) when accessing the ROM as I noticed that although it was spec’d as 1 MHz it was only actually one half of the cycle that was critical.

We also wrote our own OS and compiler back end (from BCPL ocode).

There is quite a difference between the two versions of “building a computer”!

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At the moment assembling out of already made parts, although I well aware such parts for RISC-V will be not available for awhile yet.

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If you want to spend an interesting hour on Hackday it’s practically a sub-culture unto itself.

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Thanks I’ll look into that.

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Thanks again guys. I just got started with learning C yesterday using this book on Wikibooks.org
https://en.wikibooks.org/wiki/C_Programming

I figure that even if I don’t do any sort of programming, I can at least learn how to compile source code and help with bringing over more Linux distros for RISC-V such as Arch Linux and Manjaro Linux once RiSC-V hardware is available.

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Worthy aspirations, good luck!

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Thanks I found learning C and using GCC to compile the source files to be easier then I expected once I found a good tutorial herer:

The hardest part was simply getting started and sticking with it. On the plus side, I also getting better at using the CLI as well.