I bought four working monochrome laptops today, 2 486 DX machines and 2 386SX, for $40.00 and a handshake. In addition I got 3 PCMCIA Ethernet cards, 2 4MB RAM PCMCIA memcards, a PCMCIA CD-ROM reader portable unit and a PCMCIA Data/Fax Modem for another ten bucks. The seller threw in two portable Canon printers (battery powered where desired) and an Ethernet power hub panel for free. I got a docking station for one of the Canon 486DX laptops, in addition this machine has a printer built-in to the side! I am not sure if I will be able to get a printer cartridge for it, have to look around.
So my hardware for the OS is pretty straightened out. Several things are clear in my mind:
1. This OS should not run in Windows, not even Win 3.1 because of speed, performance and reliability issues. It was probably a mistake for me to spend so much time working on my prior version of CD Commander in Borland C++ Builder for a target W95-98 platform. Windows is crap for anything real-time and anything that has to perform well without fail. It also runs like a dog even on a modern machine, much less an old laptop.
2. To really take advantage of the hardware, the application has to run in 32 bit protected mode, whatever it is. I still have my entire WATCOM C++ development environment with the Sci-Tech VESA libraries if it comes to that.
3. It's a good idea to aim really low in terms of onboard memory requirements, to make it run on anything. The problem with Linux is that it is not really practical with less than 80 MB of storage available and even that is too ambitious. I need to write something that will work in what were once considered to be tiny RAM machines of as little as 4 MB storage either as a Flash card or in memory from some other resource plugged in.
4. In order to appeal to everybody everywhere, I have to write a Vault Operating System that can be implemented and used by nearly everybody everywhere on zero budget junk hardware that they can beg-borrow-steal. The more modest the better. Maybe I should be aiming for XT specifications, 512K RAM + DOS as a basis for something like VBDOS. It's no good writing a fantastic multiuser networked system if it requires $10,000 upfront and every terminal has to be a 1 GHX Win XP machine running on 4 gigs of RAM. People have better things to spend their prep money on. On the other hand, if it's cheap/simple/easily maintained and implemented, it could become ubiquitous.
5. There's an incredible amount of free dos software out there, including things like audio inputs for Sound Blaster you can hook up the headset/speaker jack for a CD-715 to in order to generate bargraphs of radiation counts. That's just one example of the sort of bargain basement ingenuity you can use running DOS programs. If you can make do with character graphic displays it gets even better.
Again, Visual Basic for DOS looks good with these requirements. The problem is that it only runs in real mode and that leaves a lot of memory wasted. Even EMS and XMS don't allow the programmer to take advantage of the power of protected mode that is available.