IBM System/23 Datamaster
Released:July 1981
Price:US$9,830 with printer
Weight:95 pounds
CPU:Intel 8085
RAM:64K max
Display:80 X 24 text
green phosphor display
Expansion:six internal slots
Storage:dual 8-inch floppy drives
Ports:current-loop serial port
printer port
OS:BASIC built-in

Please, stand at attention in the presence of the (horns sound - "ta da!") - IBM System/23 Datamaster!

This large, extremely heavy (95 lbs/43 kg) all-in-one desktop computer system, was designed to be taken out of the carton, set up, checked out and operated by first-time users.

The Datamaster combined word processing and data processing in a single machine to give small businesses the big benefits of information processing.

The same engineers who design the Datamaster went on to help designed the IBM PC, the computer system which started the PC revolution which exists today.

The power supply and motherboard both pull-out from the back of the system for easy access. This can be done whether or not the system cover has been removed.

As you can see, the 8-inch floppy drives are very large, with several heavy-duty components. These large and heavy drives are rather uncommon for 1981 - most other computer systems had switched to 5 1/4-inch drives by this time.

Seen to the left is a memory board which plugs into the motherboard.

It is very unusual, with all of the chips piggy-backed with an identical one.

This is either to double the memory capacity, or to add redundancy, as early RAM chips apparently failed (open) prematurely, and doubling them up greatly increased the lifespan of the memory board.

Related Links

  • Datamaster from

  • Partial History of the IBM Computers

    • 1967: IBM builds the worlds first floppy disk.
    • 1967: IBM introduces the worlds first 8" floppy disk.
    • 1973: IBM introduces the IBM 3340 hard disk unit, known as the Winchester.
    • 1975: September - IBM's Entry Level Systems unit unveils "Project Mercury", the IBM 5100 Portable Computer.
    • 1981: September - IBM releases the IBM 5150 PC Personal Computer.
    • 1982: April - Eight months after the introduction of the IBM PC, 50,000 units have been sold.
    • 1982: May - Microsoft releases MS-DOS 1.1 to IBM, for the IBM PC.
    • 1982: June - The first IBM PC clone, the MPC, is released by Columbia Data Products.
    • 1982: August - After one year of production, IBM ships the 200,000th IBM PC.
    • 1982: November - Compaq Computer introduces the Compaq Portable PC, the first 100% IBM compatible. It cost Compaq US$1 million to create an IBM-compatible ROM BIOS that did not violate IBM's copyright.
    • 1982: At the West Coast Computer Faire, Davong Systems introduces its 5MB Winchester Disk Drive for the IBM PC, for US$2000.
    • 1983: March - IBM announces the IBM PC XT, with a 10 MB hard drive, 128KB RAM and a 360KB floppy drive. It costs US$5000.
    • 1983: November - IBM announces the IBM PCjr. It is US$700 for the bare configuration.
    • 1984: February - IBM introduces the IBM Portable PC.
    • 1984: March - IBM ships the IBM PCjr. It uses the 8088 CPU, 64KB RAM, and one 5.25-inch disk drive, but no monitor. It costs US$1300.
    • 1984: August - IBM announces the PC AT, for US$4000-6700.
    • 1985: April - IBM abandons production of the IBM PCjr.
    • 1986: April - IBM announces the IBM PC Convertible, 80C88-based, 256K RAM, and two 720K floppy disks, for US$2000.
    • 1986: April - IBM discontinues the IBM Portable PC.
    • 1986: September - IBM announces the IBM PC-XT Model 286, with 640KB RAM, 1.2MB floppy drive, 20MB hard drive, serial/parallel ports, and keyboard for US$4000.
    • 1987: IBM discontinues the IBM PC (model 5150) line.
      Source: Chronology of Events in the History of Microcomputers

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