IBM mainframe

The first computer I worked with professionally was the IBM System 370

These were big boxes, the size of large refrigerators. I learned a lot in those days, about real storage, virtual storage, virtualization, machine code, S/370 assembler language, COBOL, file structures, etc, etc. 

During this time, from the late 70’s to the early 80’s, the foundation for my entire carrier in ICT was laid. I do have fond memories of that time, despite or perhaps even because the all-nighters we sometimes had to pull…


Now recently I started again with a beautiful piece of emulator software called Hercules. This software can be installed on MacOS, Linux and Windows, and it simulates a 370 type mainframe hardware environment. On this emulated computer one can run the original operating systems that were given in the public domain at some point in time.

So, I installed one of those on my Hercules installation, the MVS 3.8 TurnKey 4- system, which runs very stable up until now.

Raspberry Pi

I tested the installation on different platforms, and now have it running on Linux on one of my Raspberry Pi’s! Despite the small hardware, it runs very smooth, proof of the amazing efficiency of these old Operating Systems!

MVS3.8 TK 4-

And here we are, just after installation, this turnkey system presents itself:

Having logged in for the first time, I am greeted by a familiar sight, the menu of the available applications for TSO (Time Sharing Option):