For most people, just getting any old microcontroller or system on chip (SoC) from our favorite – or cheapest – vendor is more than good enough. But if you’re really into high assurance computing where every transistor has to be accounted for, you got a bit of a problem. This is basically why [Andrew “Bunnie” Huang] pitched in and had the Baochip-1x produced.
This SoC’s design is based heavily on the FPGA-based CPU in the Precursor device, which itself is claimed to be a fully verifiable communicator design. Since it does have an MMU, you can run any software on it that supports the RV32IMAC RISC-V instruction set, with a Coder’s Guide available for those who might feel interested in this SoC, along with the SystemVerilog and Verilog-based sources.
In addition to the DIY assembly process, you can even get a physical hardware version, including the ‘Dabao’ evaluation board with a very Raspberry Pi Pico-shaped form factor. Inside this SoC is a single-core, 350 MHz VexRISC-V core, 4 MB resistive RAM (RRAM) and 2 MB of SRAM, along with a whole heap of security-related features.