The Xerox 820 was an 8-bit desktop computer sold by Xerox. The computer featured floppy disk drives for mass storage, and used the CP/M operating system. The design of the microprocessor board was a licensed variant of the Bigboard computer.

The Xerox 820 was released in June 1981. The Xerox 820-II followed in 1982, featuring a Z80A processor clocked at 4.0 MHz. The units were priced starting at $3000.

The processor board was located inside the CRT unit, and included the Z80A, 64K of RAM (with optional expansion up to 32-34K), and 6-8K of ROM (expandable). The CRT itself was a 12-inch, 24-line, 80-character (7x10 dot matrix) white-on-black monochrome display, with software-selectable variations such as reverse video, blinking, low-intensity (equivalent to grey text), and 4x4-resolution graphics.

The 820-II came with a 96-character ASCII keyboard with a 10-key numeric keypad and a cursor diamond which otherwise defaulted to control characters 'A-D. It also included "Help" and "Line Feed" keys, and attached to the back of the CRT unit with a thick cable.

The 820-II included two RS-232 25-pin serial ports (including one intended for a Xerox 620 or 630 printer or compatible) and two optional parallel ports which could be added via an internal pin header with either an official Xerox cable or one's own modification.

A typical 820-II came with CP/M 2.2, a diagnostic disk, a copy of MicroPro's WordStar suite, and Microsoft's BASIC-80.

Manufacturer: Xerox
Date: 1982

This exhibit has a reference ID of CH3139. Please quote this reference ID in any communication with the Centre for Computing History.