The Hercules System/370, ESA/390, and z/Architecture Emulator
Hercules is an open source software implementation of the mainframe System/370 and ESA/390 architectures, in addition to the latest 64-bit z/Architecture. Hercules runs under Linux, Windows, Solaris, FreeBSD, and Mac OS X.
Hercules is OSI Certified Open Source Software licensed under the terms of the Q Public Licence.
Hercules was created by Roger Bowler. Jay Maynard (“the Tron Guy”) was the maintainer from 2000 to 2012. Jan Jaeger designed and implemented many of the advanced features of Hercules, including dynamic reconfiguration, integrated console, interpretive execution and z/Architecture support. A dedicated crew of programmers is constantly at work implementing new features and fixing bugs.
To find out more about Hercules, follow these links:
To download the current release version, use the following links:
What people are saying about Hercules
I do miss my mainframe a lot, and playing with Herc sure brings back
memories. Just seeing the IBM message prefixes, and responding to
console messages again was a wonderful bit of nostalgia!
I have installed your absolutely fantastic /390 emulator.
You won't believe what I felt when I saw the prompt.
Congratulations, this is a terrific software.
I really have not had such a fascinating and interesting
time on my PC lately.
Such simulators have been available for a long time. One of the most
complete (up to modern 64-bit z/Architecture) is hercules.
An apparently excellent emulator that allows those open source
developers with an "itch to scratch", to come to the S/390 table
BTW grab a copy of Hercules and you can test it at home.
It's a very good S/390 and zSeries (S/390 64bit) emulator..
It works even better than I imagined.
Hercules is a fine piece of software!
Hercules is a systems programmer's dream come true.
Aside from the electric trains my parents got
me in 1953, this is the best toy I've ever been given,
Congratulations to you and your team on a fine piece of work!
Congratulations on a magnificent achievement!
For anyone thinking running Hercules is too much trouble or too hard
or whatever, I came home from work one day and my 13 year old 8th
grade son had MVS running under VM under Hercules on Linux. He had
gotten all the information about how to do this from the Internet.
When he complained about MVS console configuration and figuring out
how to get it to work with VM, I knew he had felt all the pain he
ever needed to feel about mainframes.
I am running a fully graphical Centos z/Linux environment on my desktop.
The Hercules emulator is an amazing feat of engineering.
I just wanted to send my compliments to the team for an excellent job!
Thanks much for making this product part of the open-source community!
I have DOS and DOS/VS running on Hercules with
some demo applications, both batch and on-line. It does bring back
some good memories. My compliments go to the Hercules team. Thank you.
This is stunning piece of work. To say that I am blown away is an
understatement. I have a mainframe on my notebook!!!!!!
P.S. Now if I can just remember my JCL
Read Moshe Bar's BYTE.com article about Hercules at http://web.archive.org/web/20010712143133/http://www.byte.com/documents/s=429/BYT20000801S0002/
For eighteen months, the IBM Redbook SG24-4987 Linux for S/390 at http://www.redbooks.ibm.com/abstracts/sg244987.html contained a chapter written by Richard Higson describing how to run Linux/390 under Hercules. Then suddenly, all mention of Hercules was mysteriously removed from the online edition of the book! Read the story of the disappearing Redbook chapter at http://www2.marist.edu/htbin/wlvtype?LINUX-VM.25658
View the foils from Jay Maynard's presentation given at SHARE Session 2880 in San Francisco on 20 August 2002 as a PDF file (815K) from http://linuxvm.org/Present/SHARE99/S2880JMa.pdf
The source code repository
The complete source code and development history for Hercules is also available via anonymous access from these git repositories:
Please note that the development repositories may contain faults which may be fixed at an unspecified later date, as well as experimental code which might not appear in any future production release.
Build instructions are contained in the source files INSTALL (for Unix) or README.WIN32 or README.WIN64 (for Windows).
Other Hercules-related sites
If you have any questions or comments please consider joining the hercules-390 discussion group at http://groups.yahoo.com/group/hercules-390.
Bug reports for the current release (together with your diagnosis of the fault, please) may be posted at the hercules-390 discussion group. Problems with the developer sandbox version should be entered into the Hyperion issue tracker at https://github.com/hercules-390/hyperion/issues.
IBM, System/370, ESA/390, and z/Architecture are trademarks or registered trademarks of IBM Corporation. Other product names mentioned here are trademarks of other companies.
Last updated $Date$ $Revision$