The MTS team made available various historical versions of MTS. Some of
the are old enough to run in 370 mode. IIRC not all of them are in a
bootable state, but I think Rich Cornwell got some of the older stuff to
run.
Rather than chase the unobtainium, it'd probably be more worthwhile to:
- See about running one of those older 360- or 370-mode versions.
- Build a replacement for ASMH that will run on various platforms (MTS,
IBM OSen, Unix, etc), and includes the patched behavior of the MTS
version.
- Work with IBM to obtain non-commercial rights to share, modify and run
ASMH. Haha.
The first could be fun -- there are some subsystems in the 6.x versions
that most currently run which were relatively late to the game.
The second would solve a fair number of problems across the IBM 3x0
emulation community. MTS is far from the only place with ASMH license
problems.
The third is presumably a "good luck, Charlie" sort of affair.
De
