Engineering:Motorola 68000 Educational Computer Board

Short description: Description of Motorola 68000 educational computer board

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

• 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

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

The price of the Motorola ECB at launch was US$495 (equivalent to $1,390 in 2019) which was relatively inexpensive for a computer with an advanced for that time 16/32-bit CPU.

Use

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.

References

MC68000 Educational Computer Board User's Manual

External links

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