3 ms·

The Kendryte is pretty limited in many ways, not least that it's permanently limited to 8 MiB of DRAM (AFAIK). The most interesting route is using an FPGA. Th

The Kendryte is pretty limited in many ways, not least that it's permanently limited to 8 MiB of DRAM (AFAIK). The most interesting route is using an FPGA. There are many examples of running RISC-V softcores on FPGAs (for example, Berkeley's RocketChip) and many boards that support a decent amount of memory (even beyond 1 GiB).

pavehawk2007 6y ago
I tried some of SiFive's evaluation cores. They limit you quite a bit unless you pay. Furthermore, many of the FPGAs worth their salt were quite expensive. The K210 in the MaixBit form is only $20, and it comes with a camera and LCD. For hobbyists, I think it's a good compromise. I looked at the Xilinx FPGAs--the ones SiFive recommends, but they're quite pricey. Which FPGAs had you had luck with?
- pcein 6y ago
  I haven't used them myself, but these boards look awesome, and they are supported by an end-to-end open source toolchain: 1. https://www.crowdsupply.com/1bitsquared/icebreaker-fpga https://www.crowdsupply.com/1bitsquared/icebreaker-fpga 2. https://www.crowdsupply.com/radiona/ulx3s https://www.crowdsupply.com/radiona/ulx3s 3. https://groupgets.com/campaigns/710-orangecrab https://groupgets.com/campaigns/710-orangecrab
- fluffything 6y ago
  I was looking at getting this Maixduino kit since it appears to be the cheapest solution that satisfies my constraints (RISCV core + WiFi): https://www.seeedstudio.com/Sipeed-Maixduino-Kit-for-RISC-V-AI-IoT-p-4047.html https://www.seeedstudio.com/Sipeed-Maixduino-Kit-for-RISC-V-... I'm not sure what's the status of programming these from Rust. I suppose that you will probably need to build your own toolchain that links the Seeedstudio libraries.
  - pavehawk2007 6y ago
    RISC-V has their own supported toolchain. You can get it here: https://github.com/riscv/riscv-gnu-toolchain.git https://github.com/riscv/riscv-gnu-toolchain.git With Rust, you can do what I did with my OS. It can compile out of the box. The kendryte has a "BSP" (base support package) that is essentially a minimal OS, but it is written in C.
    - fluffything 6y ago
      Yeah, I was thinking more about what to do with the OS afterwards. That board has lots of things on it, including wifi, so I'll probably would like to use some of that. It would be unfortunate to have to re-implement the wifi driver in Rust, but I suppose I'll just have to link parts of the C toolchain instead, creating Rust wrappers, etc.
- FullyFunctional 6y ago
  Well, FPGA are more flexible but cost more than a cheap microcontroller that is true. There are way too many good options, but to pick one with a fantastic community: ULX3S

pavehawk2007 6y ago

I tried some of SiFive's evaluation cores. They limit you quite a bit unless you pay. Furthermore, many of the FPGAs worth their salt were quite expensive. The K210 in the MaixBit form is only $20, and it comes with a camera and LCD. For hobbyists, I think it's a good compromise. I looked at the Xilinx FPGAs--the ones SiFive recommends, but they're quite pricey. Which FPGAs had you had luck with?

pcein 6y ago
I haven't used them myself, but these boards look awesome, and they are supported by an end-to-end open source toolchain: 1. https://www.crowdsupply.com/1bitsquared/icebreaker-fpga https://www.crowdsupply.com/1bitsquared/icebreaker-fpga 2. https://www.crowdsupply.com/radiona/ulx3s https://www.crowdsupply.com/radiona/ulx3s 3. https://groupgets.com/campaigns/710-orangecrab https://groupgets.com/campaigns/710-orangecrab
fluffything 6y ago
I was looking at getting this Maixduino kit since it appears to be the cheapest solution that satisfies my constraints (RISCV core + WiFi): https://www.seeedstudio.com/Sipeed-Maixduino-Kit-for-RISC-V-AI-IoT-p-4047.html https://www.seeedstudio.com/Sipeed-Maixduino-Kit-for-RISC-V-... I'm not sure what's the status of programming these from Rust. I suppose that you will probably need to build your own toolchain that links the Seeedstudio libraries.
- pavehawk2007 6y ago
  RISC-V has their own supported toolchain. You can get it here: https://github.com/riscv/riscv-gnu-toolchain.git https://github.com/riscv/riscv-gnu-toolchain.git With Rust, you can do what I did with my OS. It can compile out of the box. The kendryte has a "BSP" (base support package) that is essentially a minimal OS, but it is written in C.
  - fluffything 6y ago
    Yeah, I was thinking more about what to do with the OS afterwards. That board has lots of things on it, including wifi, so I'll probably would like to use some of that. It would be unfortunate to have to re-implement the wifi driver in Rust, but I suppose I'll just have to link parts of the C toolchain instead, creating Rust wrappers, etc.
FullyFunctional 6y ago
Well, FPGA are more flexible but cost more than a cheap microcontroller that is true. There are way too many good options, but to pick one with a fantastic community: ULX3S