Stratos (computer)
The Stratos was a Z80-based microcomputer introduced by Symbiotic Systems, Inc., in 1981.
Background and development
The Stratos was designed by Stewart Earnest and Ray McKaig of Symbiotic Systems, Inc., a company originally based out of Woodland, California, and later relocated to Santa Cruz, California. Symbiotic Systems previously released the Syncron 8, a S-100 bus–based computer running the Intel 8080 microprocessor and featuring a backplane motherboard with twenty card slots. The 8080 is housed on a card that features PROMs, one of which has a bootstrap loader allowing the user to load software via floppy disk or data cassette, while the other has a 512-KB PROM flashable by the user. The Syncron 8 can take up to 12 KB of RAM and has a keyboard interface allowing users to directly interact with the computer without the need for a terminal. A television could be used as a display for the computer with the use of a composite cable. The Syncron 8 was regarded as a hobbyist or industrial computer.Specifications
The Stratos by contrast is a general-purpose, turnkey, single-board computer, built from a six-layer printed circuit board and powered by a Zilog Z80 microprocessor clocked at 4 MHz. The computer comes with 64 KB of conventional RAM and 16 KB of additional RAM, the latter programmable as either disk-cache memory, as conventional memory, as video memory, or as a RAM disk. The computer also comes with a 2-KB EPROM. The computer's BIOS chip was custom written by Symbiotic Systems.The included software package comprises CP/M version 2.2, the Spellbinder word processor, either CBASIC or a Pascal compiler, Reminder, Autophone, a personal financing application, and a medley of bespoke programs. Reminder is a task-scheduling utility that took advantage of the computer's built-in real-time clock to executive certain programs and directives based on a 99-year calendar. Autophone is an auto-dialer/answering utility that can issue DTMF signals or pulses through a telephone line to automatically place phone calls; it can also automatically answer incoming calls if it detects one on the line. One of the Stratos' bespoke programs is Font, a bitmapped font editor that can redefine any of the 256 memory-mapped 8-by-9-matrix characters of the on-screen font to any shape, either with a keyboard or with an optional light pen.
The Stratos was optioned with either one or more 5.25-inch or 8-inch floppy disk drives. It can address up to 5 MB of floppy storage. The computer's power supply unit is switched-mode and was reported to run at 80 percent efficiency in 1981, negating the need for internal fans. The system unit and included keyboard are housed in a teak enclosure. The computer's lack of electromagnetic shielding reportedly made the computer prone to radio-frequency interference.