how to.... Do’s and do not

Will the very old Dos programs run on new computers?   I found some of my old Ms-dos operating system disks. I fired up Dos ver1.1 on my 2gz compaq machine. The Dos fired up and ran fine. As for Ms-dos 2.1 and 3.3, Dos 5.0 and 6.22 no problem. I got an old hard drive and installed  ms-dos 2.1. The install only took  a minute or two. I then installed the other Dos Disks one at a time. Still no problems. All of the operating systems fired up and ran as they should. I then tried out some of the very old software. Most of it worked well enough. Software that used the older video CGA monitor didn’t do so will. Three out of the ten that I tried failed to work. The old CGA games gave me even more problems. The newer stuff seem to work more reliability. There is  thousands of Dos programs out there that work perfectly fine. The question then becomes can there be a simple environment that will run new and old Dos software on modern computers.

Here is the dilemma.

 Most of today computer do not have a floppy drives. Older OS’s were happy to boot off of a floppy drive and switch over to the C drive run files just as though the system had booted on the C drive. Windows NT/2000/XP can booted off of a CD but not a floppy. Most windows partition the C: drive to take up all of the space on the drive, no matter what size it is,  this leaves no room to add other operating systems. OK so we can’t use a floppy drive and the hard drive is full.

Here are some possible answers

1. Use an old PC computer with a 5.25” floppy drives. These old PC’s runs in real mode only which covers DOS type environments that use the direct hardware access environment which will be almost all of them. The down side is that these older PC’s can’t assemble the DOS code with the method that is used here at PDP. Yes it is possible to use an older real mode assembler like A86, IBM asm ver 1.0 and many others to do the job. But they can be difficult to write code for and assemble the code they use multi steps to complete to job. Also the code can get very wordy. Unforchanitly the code used here at PDP won’t work with other assemblers
P.S There is no standard code that will work with all of the different assemblers

 2. Use an older 80386 PC computer. with a 5.25” and or 3.5” floppy drive. Having a 1.2 mb floppy drive and a 1.44 mb floppy drive in most cases would be the best combination. This setup has many advantages over the one above. First it can handle the newer 3.5” floppy drives. It can handle a CD ROM drives. It will boot and run your disk that you just made. And it can assemble all of your code using the NASM assembler. This type of setup may be a good middle of the road setup. I recommend that you use FreeDos for all of your work if you can. If you have Ms-Dos 6.22 that will work also. You may be tempted to install windows 95 or 98 or it may already have windows on it. If you are one that just has to have  win 95/98, you will also need Ms-Dos 3.3 -6.22 to be installed. If you doing a fresh install, install Ms-Dos x.x on the c drive then install win 95/98 over top Ms-Dos. Windows 95/98 will see Ms-Dos and keep it. A startup menu will be presented  you at startup. You then can select window, widows dos or Ms-dos. Select Ms-Dos to do all of your PDP work. Select window to run windows. If you install winows 98se you then can use USB thumb drives and most CD's. Window sees all of your Dos files so you can move then to a CD or thumb drive. Some Internet access is also possible.
Note: Some PDP stuff will work out or Windows Dos and even less will work  out of windows Dos shell. So to be sure thing work correctly, use Ms-Dos on all of your PDP projects

 3.  Use an older 80486 PC computer or pentiumn I, II  and a 3.5” floppy drive.  If windows 95/98 is installed, you will also need Ms-Dos x.x installed. although it is possible to add Ms-Dos, to your windows, I think it is far easier to do a fresh install. The rules are the same as in above. But the you will have faster internet access.

4. If you have windows 2000. Do a Fresh install. start by install Ms-Dos then install windows 95/98, Then windows 2000. All three operating will be available from the startup menu. You must install all three operating system in the correct order. windows will make the correct boot menu for you. (startup menu) This is a great setup because you can get on the internet with reasonable speed. In this way you can download your projects. then copy them over to the DOS partition. then startup  DOS and assemble then and make the boot disk, restart the system and test the boot disk all with one machine.

5. If you have window XP or above, you can make it a triple boot like above or a quad boot having Ms-Dos windows 98, 200, XP all on the same drive. no need to use boot master or other multi boot programs unless you want to. windows will do a resenable setup for automatically

6. I call it the back door method
It uses the CD ROM drive for the boot disk and a USB memory pin stick for the hard drive. The CD ROM drive can be made into a boatel drive and made to look like the A: drive. The A: drive then can jump start the USB E: drive. Just like the old times, when you could not startup Ms-Dos, you would slip in a Emergence boot disk. This is an OK way to do things If you do no want to spend the time rebuild your computer system. If you have a CD ROM drive and a USB port and thumb drive. The rest is of the software is free. You won’t need a valid copy of XP, 2000, 98, and Ms-Dos like in option 5 above.
Go to the download page and download the PDP boot CD.