An Exatron Stringy Floppy (cover removed) designed for use with the TRS-80 Model 1 The Exatron Stringy Floppy (or ESF) is a continuous-loop

tape drive A tape drive is a data storage device that reads and writes data on a magnetic tape. Magnetic-tape data storage is typically used for offline, archival data storage. Tape media generally has a favorable unit cost and long archival stability. ...

developed by Exatron.

History

The company introduced an S-100 stringy floppy drive at the 1978

West Coast Computer Faire The West Coast Computer Faire was an annual computer industry conference and exposition most often associated with San Francisco, its first and most frequent venue. The first fair was held in 1977 and was organized by Jim Warren (computer specia ...

, and a version for the

Radio Shack RadioShack (formerly written as Radio Shack) is an American electronics retailer that was established in 1921 as an amateur radio mail-order business. Its parent company was purchased by Tandy Corporation in 1962, which shifted its focus from ma ...

TRS-80 The TRS-80 Micro Computer System (TRS-80, later renamed the Model I to distinguish it from successors) is a desktop microcomputer developed by American company Tandy Corporation and sold through their Radio Shack stores. Launched in 1977, it is ...

in 1979. Exatron sold about 4,000 TRS-80 drives by August 1981 for $249.50 each, stating that it was "our best seller by far". The tape cartridge is about the size of a business card, but about thick. The magnetic tape inside the cartridge is wide.

Format

There is no single catalog of files; to load a specific file the drive searches the entire tape, briefly stopping to read the header of each found file. The tape loop only moves in one direction, so a file that starts behind the current location cannot be read until the drive searches the entire loop for it. The device is capable of reading and writing

random access Random access (also called direct access) is the ability to access an arbitrary element of a sequence in equal time or any datum from a population of addressable elements roughly as easily and efficiently as any other, no matter how many elemen ...

data files (unlike a datacassette). If a record being sought has been overshot, the drive advances the tape until it loops around to the beginning and continues seeking from there. According to ''Embedded Systems'' magazine, the Exatron Stringy Floppy uses

Manchester encoding In telecommunications and data storage, Manchester code (also known as phase encoding, or PE) is a line code in which the encoding of each data bit is either low then high, or high then low, for equal time. It is a self-clocking signal with no ...

, achieving 14K read-write speeds and the code controlling the device was developed by Li-Chen Wang, who also wrote a

Tiny BASIC Tiny BASIC is a family of dialects of the BASIC programming language that can fit into 4 or fewer KBs of memory. Tiny BASIC was designed by Dennis Allison and the People's Computer Company (PCC) in response to the open letter published by Bi ...

, the basis for the TRS-80 Model I Level I BASIC.

Reception

In the July 1983 issue of '' Compute!'s Gazette'', the Exatron Stringy Floppy for the

VIC-20 The VIC-20 (known as the VC-20 in Germany and the VIC-1001 in Japan) is an 8-bit entry level home computer that was sold by Commodore International, Commodore Business Machines. The VIC-20 was announced in 1980, roughly three years after Commod ...

and the

Commodore 64 The Commodore 64, also known as the C64, is an 8-bit computing, 8-bit home computer introduced in January 1982 by Commodore International (first shown at the Consumer Electronics Show, January 7–10, 1982, in Las Vegas). It has been listed in ...

was reviewed. Calling the peripheral "a viable alternative" to tape or disk, the magazine noted that "under ideal conditions, a Stringy Floppy can outperform a VIC-1540/

1541 __NOTOC__ Year 1541 ( MDXLI) was a common year starting on Saturday of the Julian calendar. Events January–March * January 4 – Leonardo Cattaneo della Volta is elected to a two-year term as the new Doge of the Republic o ...

disk drive".

Texas Instruments Texas Instruments Incorporated (TI) is an American multinational semiconductor company headquartered in Dallas, Texas. It is one of the top 10 semiconductor companies worldwide based on sales volume. The company's focus is on developing analog ...

licensed the Stringy Floppy as the Waferdrive for its cancelled TI 99/2 computer and a Compact Computer 40 peripheral which never shipped.

Use and distribution

The Exatron drive was initially used in the Prophet-10 music synthesizer and was later replaced with a micro-cassette drive from Braemar, reportedly due to unreliability and poor mutual compatibility of the former. Cartridges, or "wafers", were available in tape lengths ranging from . Known data capacities/tape length are: 4 kB/5 feet, 16 kB/20 feet, 48 kB/50 feet, and 64 kB/75 feet. One complete cycle through a tape takes 55 to 65 seconds, depending on the number of files it contains.

References

External links