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Show HN: I designed a 24-trit balanced ternary RISC processor on FPGA (zenodo.org)
1 points by claudio_mos 88 days ago
2 comments
claudio_mos 88 days ago
I'm the author. The 5500FP is a complete 24-trit balanced ternary RISC processor implemented on an Efinix Trion T20F256 FPGA, with a custom open hardware development board (GargantuRAM).

The ISA is fully documented, including instruction formats, privilege model, and a trit-based data hierarchy.

Full ISA docs and hardware at https://www.ternary-computing.com/docs/assembly/ISA/doc_inde...

Mainboard OpenHardware: https://github.com/Ternary-Computer-System/GargantuRAM Very simple OS: https://github.com/MOS5500/GRam_OS

Happy to answer questions on this architecture.

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brucehoult 87 days ago
Very interesting.

The first question has to be: why?

I don't see any rationale or explanation of the thinking. Is it purely an exercise? Exploration? Is there some algorithm space in which it has an advantage over binary?

Is there a compiler?

How does it compare on Dhrystone or Coremark per LUT compared to a RISC-V core of similar size on the same FPGA?

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claudio_mos 87 days ago
> The first question has to be: why?

There are many reasons. The main one is that no architecture exists that models such a complex ternary processor. At most, there are "on paper" implementations of much less complex architectures; no one has addressed the problem at this level. Having a complete architecture and its hardware implementation now allows us to start developing software on something other than an emulator.

> ---- I don't see any rationale or explanation of the thinking. Is it purely an exercise? Exploration? Is there some algorithm space in which it has an advantage over binary? > -----

No, it's a processor that's available now, both the current hardware implementation (on FPGA) and the Verilog/VHDL description for implementation on other architectures (ASIC?), as well as the specifications made available under license.

>---- Is there a compiler? >----

Hmm, but I mentioned it in the paper; currently, a working cross-assembler (obviously) and a high-level language based on Rust are being designed/built.

>---- How does it compare on Dhrystone or Coremark per LUT compared to a RISC-V core of similar size on the same FPGA? >----

This is an interesting question; the answer is: currently, no. We intend to provide (soon) comparative tests of this type.

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