It is mini Linux or mimix
MINIX is a free UNIX clone that is available with all the source code. Due to its small size, microkernel-based design, and ample documentation, it is well suited to people who want to run a UNIX-like system on their personal computer and learn about how such systems work inside. It is quite feasible for a person unfamiliar with operating system internals to understand nearly the entire system with a few months of use and study.
http://www.oldlinux.org/Linux.old/Minix/minix.html
http://www.china-cpu.com/Product/index.htm