Overview

VAM - Virtual Alpha Micro - is a pair of emulators for the first two generations of Alpha Micro computers.

The first generation being their S-100 boards using the Western Digital WD-16 chip set. This generation ran Alpha Micro's AMOS operating system and the VAM emulator for this generation, called AM100, primarily targets their final 5.0 release of AMOS.

The real machine in my thoughts as I developed this first generation emulator was a homebrew S-100 system I put together in the mid 80's.

It ultimately consisted of a 22 slot TEI chassis with

• a 'short' 2 card AM-100 cpu set,
• a couple of Measurement Systems and Control dmb-6400 ram memory cards,
• a Cromemco 8k ByteSaver II rom memory card,
• a AM-300 6 port serial card,
• a AM-120 auxiliary input card,
• a AM-200 floppy disk controller attached to a Persci 277 8" dual floppy disk drive,
• a Konan smc-100 2 card smd disk controller set attached to a Priam 3350 30mb hard disk.

Alpha Micro's second generation was initially S-100 board based but later evolved into various integrated systems, all using Motorola 68000 family chips. This generation ran their AMOS/L operating system and the VAM emulator for this generation, called AM1200, primarily targets their 1.3 release of AMOS/L.

In the day I upgraded from my WD16 system to an AM-1000 shortly after Alpha Micro introduced them. Some years later I upgraded to a Mac and exited the Alpha Micro ecosystem by which time it had grown to a bit under 1mb ram, a 10 mb hard drive, a 5.25" floppy diskette drive and 10 ports.

When decades later I decided to get back to my roots I went looking for something like it, but I never found one.

What I did find and currently own is a real (and working) AM-1200. 4mb ram, 400mb hard drive, 14 ports. The hard drive is long dead, but the zuluscsi I replaced it with is WAY better!

My choice of AMOS & AMOS/L releases for VAM is based on having backup copies of   those I ran on my own AM100 & AM1000 systems in the 1980's when I developed and sold system software for them.

I developed VAM in C for the Linux platform using the ncurses text screen handling package. It is distributed as source. The executables must be built on the target system. This is not as limiting as it may seem. Since Linux has become so widely available VAM can easily be build and run on Windows or Mac systems, or even on Android phones!

Both emulators provide a full multi-user experience. Multiple terminals are simulated in ncurses panels, with keyboard ALT key sequences used to switch between them. Each simulated terminal can be logged to an external file, and each simulated terminal can be accessed using a telnet connection in parallel to its ncurses panel.

Both emulators normally perform far faster than the legacy hardware, even on the smallest Linux-like systems, but are able to limit performance to provide a legacy feel if desired.

Both emulators are customized using ".ini" files to provide for such things as installed memory size, number of terminals and AMOS/AMOSL startup file name. With a simple startup option you can bring up an emulated environment with just one terminal or an environment with a dozen or more terminals and full print spooling and batch job support.