IBM Personal Computer

IBM introduced its Personal Computer to much fanfare on August 12th, 1981. The PC was developed in an astoundingly short time (under 1 year) by a “skunkworks” project at IBM’s Boca Raton Florida facility.

One significant reason for the rapid development cycle was the use of “off the shelf” parts for things like disk drives, processors, memory and the like.

Another “off the shelf” component used on the PC was IBM’s Operating System software – PC DOS. This product was licensed from Microsoft after the IBM development team were unable to secure a license for CP/M. The use of Microsoft’s product on this machine helped catapult an already successful company into its current dominant position.

The PC pictured here is one of two in my collection. This is an original PC variant with a 64K motherboard (as opposed to the later 256K motherboards) and version 1.0 ROMs. It normally has a color graphics adaptor (CGA) and an IBM 5153 Color Monitor as well as a multi-function card and some other accessories although the Monochrome monitor (IBM 5151) and IBM Monochrome/Printer Adapter card are probably more correct for the machine. The system has a full suite of original IBM documentation including the 1.0 versions of DOS, BASIC and the IBM PC Guide to Operations.

Reprinted with permission from Vintage-Computer.com

Microsoft Adventure

I have lots of original software from IBM and other sources including CP/M-86, VisiCalc, PFS:Write and much of the original IBM library of games and educational software including the BASIC Primer, Typing Tutor, Adventure and the “Microsoft Decathlon.”

Reprinted with permission from Vintage-Computer.com

Lots of Microsoft Docs

I also have the IBM PC Technical Reference and IBM PC Maintenance and Service manuals.

Reprinted with permission from Vintage-Computer.com

IBM PC manuals

Both of my PCs have all of their original manuals, as shown here. The three manuals to the right are all 1.0 versions, including DOS 1.0 with the original DOS disk.

Reprinted with permission from Vintage-Computer.com

IBM PC Keyboard

The IBM PC Keyboard was a very sturdy, well designed 83 key model that had far better key placement and a better feel than any other low-cost computer of its day. IBM did everything they could to sell the ideas of “professional” and “sturdy” with their machines and they succeeded without question. Even the function keys were a hit!

Reprinted with permission from Vintage-Computer.com

IBM 5.25 inch floppy drive

IBM made the PC with as many off-the-shelf parts as possible. That didn’t stop them from stamping them with their name and logo, though. This is a standard Tandon 5.25″ disk drive except for that IBM logo.

Reprinted with permission from Vintage-Computer.com

Reciept for my first computer

IBM sold the original PCs for around $1,600, but that was just an advertising price for the 16K system unit with a keyboard. Once you added a video adapter, some RAM and a disk drive or two you could easily climb to double that price. My first PC was purchased by my father and cost nearly $2,800. It had a single disk drive and 64K of RAM with a CGA card to be hooked into my TV set. I eventually got a black and white composite monitor so I could see 80 columns and a Quadram Quadboard that allowed me to expand the PC to nearer its 544K limit.

Reprinted with permission from Vintage-Computer.com

DOS 1.0 disk label

Perhaps my favorite aspect of this original IBM PC is the fact that I still have my DOS 1.0 manual and disk with it.

Reprinted with permission from Vintage-Computer.com

DOS 1.0 Running

DOS 1 was such a crude and simple operating system as compared to later versions or even CP/M. It was, however, easy to learn and starting from 1.0 meant that I only needed to learn a bit of new stuff with each iteration.

DOS 1.0 did have a nasty math bug, though, that was fixed by a patch – version 1.05. I’ve got a copy of that as well. IBM never officially released that version, however. It was just a bridge version until 1.10 could be shipped with the fix and some new features.

Reprinted with permission from Vintage-Computer.com

DOS 1.0 Booting close up

On boot DOS would ask for the date and then drop you to an A> prompt. There was no colon and there was no C> because the original PC wouldn’t support hard drives or sub directories.

The PC also didn’t have any sort of BIOS configuration utility. The system was configured by setting up a couple of sets of dip switches on the motherboard. One switch indicated whether you had a monochrome or color card installed. The one next to it indicated the default video mode (40 or 80 column.) Others set memory size.

Reprinted with permission from Vintage-Computer.com