First microprocessor-based computer built by Sol Libes, and his students, in 1973

The computer used the  Intel 8008, the first 8-bit microprocessor.  The system had 1KB of static RAM, a bus system for expansion, 1 parallell input/output port for process control, and one serial port for connection to an ASR33 Teletype.  The microprocessor was very primative and lacked a memory stack and interrupts, introduced later with the Intel 8080.

The circuitry was designed by Johnathan Titus, a graduate student at Virginia Polytechnic Institute.  Titus wrote a construction article that appeared in Radio-Electronics magazine.  He called the computer the Mark-8.

The computer had a front panel with LEDs to display the memory address, the contents of the registers, and control functions.  It was built using a chassis, power supplies, switches, and lamps from an old obsolete GE mainframe computer.

The system was used for process control experiments.  Programs, written in hexidecimal code, were entered using the switches and lights on the control panel   A small program was written to load and store programs from, and to, the Teletype.

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