Retro Tiny Multitasking system - for Z80 based computers

The RTM/Z80 project is intended to offer to the retro-computer hobbyists and to anyone willing to learn about multitasking systems the necessary resources needed to understand and learn the basics of this interesting but difficult area of software engineering.

Nothing compares to learning through practice, and I hope that using RTM/Z80 will help.

I was “exposed” to the “multitasking” topic some 40 years ago.

Back in 1978, as a programmer, I was allowed to use a computer named PDP-11, built by the late Digital Equipment Corporation, using RSX-11M as operating system. This was one of the first good multitasking, real-time operating systems ever designed.

Also, my job included programming an INTEL 8080 based computer.

I managed to write for this INTEL 8080 computer a small kernel (less than 8 Kbytes), containing multitasking support, I/O drivers (on interrupts) for the real-time clock, serial console, digital and analog inputs/outputs, punched paper tape (!) reader, etc.

It was used in Romania until the late 80’s in various industrial projects.

40 years after, I switched to ZILOG Z80, using the occasion provided by the creators of the RC2014 home-brew Z80-based computer, and I tried to re-build my old multitasking kernel on this new Z80 environment.

This is how the RTM/Z80 project started.

Some months later, I finished my first version of RTM/Z80 and I opted to make-it accessible to anyone interested.

In my opinion, it is a very good tool if you want to learn about multitasking.

I consider that, when someone tries to learn something connected to complex software systems, the best way is to be provided with all the possible resources, including the source code, a working hardware-software system, user manuals and implementation examples or demo programs.

Therefore, all the parts of this project, including the source code, are made accessible to anyone.

Here is a link to the RTM/Z80 GitHub project : https://github.com/Laci1953/RTM-Z80