The first production RISC-V portable?

Yes, there have been various one-off RISC-V kinda-portables, just like there have been various one-off RISC-V kinda-workstations. But it was inevitable a production "RISC-V PC" would become available, and now there's a new first, a RISC-V version of the Clockwork DevTerm portable.

The DevTerm series is clearly inspired by the Kyotronic 85 family, which many people will remember in the form of the TRS-80 Model 100. This warms my heart because an NEC PC-8201A (the other white meat) was my one and only portable computer for a month when I was overseas in Malaysia and Singapore in 2000. (It acquitted itself fabulously, for the record.) The keyboard is unfortunately smaller (one review of the ARM version compared it to an HP 200LX, which is a small keyboard indeed) and it's not touch-enabled, but the machine is very modular and apparently all that was necessary to go R5 was a redo of the OS and a new CPU-memory card (which you can buy separately for anything that will accept a Raspberry Pi compute module form factor). The CPU appears to be an Allwinner D1 containing a OpenXuantie C906, a 1GHz RV64IMAFDC(V)U single core with 1GB of memory onboard. There is no GPU, just a framebuffer.

Bluntly, these are underwhelming specs (the specs for the HiFive Unmatched didn't get my sizzle zizzled much either), and even the lowliest 4-core POWER9 Blackbird or T2 Lite would smash a HiFive into itty bitty little RISC bits. Against this, well, I think my iBook G4 wouldn't have much to worry about. But there's no portable option for OpenPOWER yet, and while a Microwatt or Libre-SoC system might get there one day — perhaps as a compatible compute module, even — this is here today, and could be a worthy mobile complement to an OpenPOWER desktop workstation. I haven't reviewed their Github exhaustively, but the C906 seems to be open-source. Plus, even though the specs are lower than their other ARM-based offerings, it's also the cheapest (the set is $239, but the CPU-memory card is just $29). This is convenient and inexpensive enough that I've squeezed a bit out of our budget to order one and I'll do a review here when it arrives. I'm unquestionably a Power ISA bigot at heart, but that doesn't mean I'm not Five-curious.


  1. The devterm only has two user-facing screws, and those are for the CPU module for extra support. Everything else is on several boards, and modular, and the CPU board is the main difference, and it is RPi CM3 compatible modules that are used for that.
    The ARM/Linux ecosystem holds it back. You cannot insert another module without altering the Linux on the uSD card, at least the DTB for the board. Without that change, the card will boot to some level, but it will be serial only over a TTL serial connector at best without those alterations.
    D1 based RISC-V has been coming out of China for just a few months now. In the current iterations AllWinner and their proprietary x86 Windows-only imaging tools are involved to write special sparse-ish img files to a physical disk. It does not do a conversion that is user-facing, and FOSS tools to deal with the format seem to just extract a bunch of files that may be useful to people doing Android development, but not something you can use dd to write to a disk.
    I would love to have a CM3-compatible FPGA version of Microwatt/LibreSoC for this. ASIC would be better, but that's probably a few years out still.
    In the meantime, do you have any emulation setups you would recommend for getting software ready-to-go for Microwatt/LibreSoC without having those chips available?

    1. It seems this SoC needs a good amount of reverse engineering and tooling then. I wonder if their simulator on github is any help developing a port? (or even works?)

    2. Not currently, and it would probably be out of date; I know little about how far Libre-SoC is, but Microwatt evolves rapidly. The goal is for it to be as OpenPOWER as anything else but I haven't seen anything that emulates at the Hostboot level or lower (QEMU starts at Skiboot: ).

    3. Here are some news of LibreSOC

  2. Ouch, a score of 32. Wonder how that compares to a Performa 6200. I'm vaguely interested in the same way I am about the Steam Deck -- a blobby handheld computer toy not really to be taken too seriously. SiFive's blob policy isn't really my thing, I'll wait for the T2080 laptop.
    Maybe I'll check in on RISC-V in 5 years. I could see it being a decent option for phones and laptops. I just don't trust SV and really, really don't trust Intel. Would be nice if more architectures came around and specialized.
    In the meantime, I'll keep using this PowerBook G4 in front of me.


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