Tektronix 405x

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The Tektronix 405x series was a series of graphics microcomputers produced by Tektronix in the late 1970s through the early 1980s. The display technology was similar to the Tektronix 4014 terminal, using a storage tube CRT to avoid the need for video RAM. The computers included a CPU, up to 32 kilobytes of RAM, keyboard, CRT and full-sized 300 kilobyte 3M DC-series high speed data cartridge (as opposed to the cassette tape drive used by the HP 9830) to the right of the CRT in a single, desktop-sized housing. Later models sported a GPIB parallel bus interface for controlling lab equipment. A simple operating system and BASIC interpreter were included in RAM. A printer was available which make copies of the screen.

External storage units were available for the 405x series computers. The smaller, desktop storage unit used single or dual Shugart 851R 10.5 inch floppy drives with 64 kilobyte floppies and the larger, 2-drawer filing cabinet sized, storage unit used a CDC 96 megabyte hard drive with the first 16 megabytes in the form of a removable disc-pack.

The 4051 microcomputer used a Motorola 6800 (an 8-bit microcontroller); the 4052 and later models used bit slice 16-bit CPUs (see 74181) for speed. These later models also had substantially larger storage tube screens that were also capable of a limited (and rather dim) write-through mode (not storing the image). The computers were popular in research laboratories and other locations where interactive plotting was important, as the storage tube video yielded much higher quality output than comparably priced RAM-based solutions of the day. The 405x series met its demise in the late 1980s as video-RAM based graphics cards became cheap and powerful enough to enable high quality plotting in commodity computers without the restrictions of the storage tube CRT.

Because the direct view storage tubes do not flicker as do conventional CRTs, and because the BASIC programming interface allowed simple, rapid prototyping of vector graphic displays, the 405x series were used in many film contexts. In particular, 405x computers can frequently be seen in early Battlestar Galactica sets.

The graphic display software was originally developed for a similar integrated desktop graphics system developed by Corning Glass. The display for this system had characteristics to the similar to those of Tektronix storage tube display. It used small pixel regions composed of photochromic glass, which could be darkened (forming a black line image) by writing, and would display this persistantly until the entire display was erased. When Corning left the market this software base was sold to Tektronix.

The original demo included an artillery game which was later adapted by high school students at Lindbergh High School in Renton, Washington to the HP 9830, and also adapted by Hewlett Packard for the HP 2647 intelligent graphics terminal demo tape. Other games for the Tektronix included Weather Wars, with users directing lightning bolts and tornados against opponents in an environment affected by wind.

[edit] External links

• Tektronix 4052 System
• Drawing lines on 4052 video