ch32fun
Open source minimal stack for the ch32 and ch5xx WCH RISC-V
...It intentionally avoids large hardware abstraction layers so developers can work closer to the device registers and technical reference manual. The project supplies lightweight headers, startup code, build tools, and many hardware examples. Its minichlink programmer supports several debug adapters and can provide GDB-style debugging and single-wire printf output. Applications can use simple GPIO, timing, ADC, interrupt, and UART helpers without adopting a full vendor SDK. The environment works on native Windows, Linux, and WSL with RISC-V GCC toolchains. Its small runtime is particularly suited to low-cost microcontrollers with very limited flash and RAM.