Installing and starting HERCULES and MVS

Table of Contents

The easy part...

installing and starting HERCULES today (2023) really is no problem at all. It can run on any commonly used OS like Windows, MacOS, and Linux. I choose my old Raspberry PI 3B as my mainframe platform. And it does the job quite well for one user. So how is it going:

My first try was running raspberry pi OS 64-bit and downloading the distribution. You can download the current up-to-date distribution from here ( The documentation says you have to unzip the zip archive in a folder of your choice and start the ./mvs script.

The first start stops with an error message. After a while, I figured out, that your raspberry pi OS has to be a 32-bit version. So I installed the 32-bit version of the OS and tried it again... And voila! here it is:

the TK4-setup for Hercules successfully started

So what next? You can press the ESC-Button to see the "other" page of this master console.

The "other" page. Press ESC to toggle to the master console

It looks like it is running. Next is to start a 3270-Terminal emulation (like c3270) to connect to the mainframe. I'm using c3270 which is part of the brew ecosystem. brew install c3270 will install a terminal emulation.

After that a

$ > c3270 hercules-pi:3270

starts a 3270-Session to the mainframe and you can logon: User herc01, password cul8tr

the logon screen of tk4

After successfull logon with herc01 you will see a screen like this:

ispf clone under tk4 mvs setup

If your screen looks a little different it my because I already installed the update on mvs turnkey 4. At the moment of writing, i didn't have a clue what this update is doing, but it sounds good and so I did it.

To Install you have to shut down the Hercules by entering "quit" in the master console (the window where you started the mvs script). Download the ROB'S update zip and unpack it in your Hercules installation directory. Directly in the root of Hercules. You have to add 2 entries into the tk4-.cnf-File. Look at the documentation of Rob's package. Then start Hercules again and you are done...

That was the easy part. But now it is getting hard for a Java programmer, that wants to start his first COBOL program. This will be part of the next session...