Comment on TKey: A reasonably secure RISC-V computer in a USB stick

• dragontamer@lemmy.world ⁨1⁩ ⁨year⁩ ago

  How so?

  The use-case is determined by power-efficiency, performance, and cost. Cost is already a loser at $72 vs $35. Performance is a loser at 18MHz vs 600MHz. What’s left is power-efficiency, but now that I know that this is an FPGA soft-core, I’m guessing the Teensy / ARM Cortex-M7 is also more power efficient.

  So the Teensy is cheaper, faster, and (probably??) more power-efficient than the RISC-V soft-core FPGA implementation here.

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  The 8-bit uCs that I like to play with (AVR, or their competitors PIC12, Cortex M0+, Cortex M32, or TI MSP430) are all in the 5mA or less range (dramatically so: some in the 5uA range if you abuse sleep / idle states severely). These 8-bitters are closer to the performance that I’d expect of the 18MHz speed and 128kB of RAM here, but I have reason to believe that the 8-bit (and 32-bit / 16-bit competitors like Cortex M0+ / MSP430) are far more power efficient than the TKey.

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