The B-Free project is a collaborative work aimed at creating a BTRON operating system from scratch, with free distribution. It is a preemptive multitasking operating system constructed through micro-kernel technology, which assumes 32-bit or higher CPUs. The BTRON operating system is a subset of the TRON project, which in turn, is a worldwide open Real Time Operating System (RTOS) specification.
B-Free 0.0.20 Released
2003-08-01 OS News 5 Comments
Link is in japanese and I can not read this site ?
Yes, it is a japanese site. It is still an OS though.
Here is some good info in English:
Here is English information on the TRON project:
I would also be happy to answer questions.
I’ve been trying to get any hard info on the TRON VLSI CPU for ages, never got anywhere. Only a description, but nothing like HDL files or even an ISA document.