Motorola 68000 Educational Computer Board

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A Motorola MEX68KECB Microcomputer, circa 1981. This microcomputer is based on a Motorola 68000 16/32-bit microprocessor.
A Motorola MEX68KECB Microcomputer, circa 1981. This microcomputer is based on a Motorola 68000 16/32-bit microprocessor.

The Motorola 68000 Educational Computer Board (MEX68KECB) was a development board for the Motorola 68000 microprocessor, introduced by Motorola in 1981. It featured the 68K CPU, memory, I/O devices and built-in educational and training software.

Hardware[edit]

  • CPU: 4-MHz Motorola 68000
  • RAM: 32KB
  • ROM: 16KB
  • 9600 baud serial port for dumb terminal connection
  • 9600 baud serial port for host computer connection
  • Parallel port for communication and printer connection
  • Audio output for tape storage
  • 24-bit programmable interval timer
  • Wire-wrap area for custom circuitry
  • Required power voltages: -12V, +5V and +12V

Software[edit]

The board has built-in 16K ROM memory containing assembly/disassembly/stepping/monitoring software called TUTOR. The software was operated using command-line interface over a serial link, and provided many commands useful in machine code debugging. Memory contents (including programs) could be dumped via a serial link to a file on the host computer. The file was transferred in Motorola's S-Record format. Similarly, files from host could be uploaded to the board's arbitrary user memory area.

Price[edit]

The price of the Motorola ECB at launch was US$495 (equivalent to $1,480 in 2021)[1] which was relatively inexpensive for a computer with an advanced for that time 16/32-bit CPU.

Use[edit]

According to the manual, for basic use only a dumb terminal and power source are required. However, it seems that in colleges the board was predominantly used in connection with a time-sharing host computer to teach assembly language programming and other computer science subjects.[2]

References[edit]

  1. ^ "The M68000 Educational Computer Board". BYTE Magazine. 1983-10-01. Retrieved 2021-08-13.
  2. ^ The Atmel AVR Microcontroller: MEGA and XMEGA in Assembly and C. Han-Way Huang. 14 January 2013. ISBN 978-1285500089.

MC68000 Educational Computer Board User's Manual

External links[edit]

  • MC68000 Educational Computer Board User's Manual [1]