Ampro Little Board
Available:March 1984
Price:US$349
CPU:Zilog Z80A @ 4MHz
Memory:64K RAM
Display:serial terminal (text)
Ports:1 parallel, 2 serial
Storage:external floppy drive(s)
OS:ZCPR3 on CP/M 2.2




Ampro described their Little Board as the world's simplest and least expensive CP/M computer. It is a complete, miniature single-board computer (SBC) optimized for compatibility with 5 1/4-inch mini-floppy disk drives.

Ampro had taken advantage of the latest in semiconductor developements, incorporating all the essential elements of a CP/M computer on one tiny board - CPU, 64K RAM, boot EPROM, battery-backed clock, terminal port, modem port, printer port, and floppy disk controller.

CP/M was the most popular computer operating system in the late 1970's and early 1980's, before Microsoft MS-DOS took-over, following the release of the IBM PC in late 1981.

The Ampro Little Board can be be mounted directly on the bottom of most mini-floppy disk drives, using the four standard threaded holes, with support for 1 to 4 single or double density 5 1/4-inch mini drives.

While the $349 Little Board is a capable single board computer, the owner still has to supply their own power supply and floppy drives. A few months later, in September 1984, Ampro released their own complete computer system, the Ampro Bookshelf Series 100, featuring the Little Board, a built-in power supply, and 1 or 2 built-in floppy disk drives. Althought the Book shelf computer was a kit that the purchaser had to put together, it was mostly assembly with no soldering required.

The Bookshelf comes with an enhanced version of CP/M 2.2, called "Friendly", which allows the user to access any program just by pointing to a menu entry on the screen. The screen displays the disk drive directory alphabetically, and you select what program to run by moving a cursor.

Three different models were available:
  • Model 121 - $895 - one 400K 48 TPI floppy drive
  • Model 122 - $995 - two 400K 48 TPI floppy drives
  • Model 142 - $1,195 - two 800K 96 TPI floppy drives

  • Since CP/M was nearing obsolescence, 1984 was very late in the game to be releasing a CP/M computer of any kind. Within a year, Ampro released additional Little Board single board computers, but these later systems were MS-DOS and PC compatible.

    Related Links

  • saundby.com
  • retrotechnology.com
  • retroarchive software
  • retroarchive hardware
  • The Wonderful World of ZCPR3
  • September 1984 InfoWorld


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