Beta Disk Interface

{{Short description|Disk interface for ZX Spectrum computers}}

File:Beta-Disk Interface card.jpg

Beta Disk Interface is a disk interface for ZX Spectrum computers, developed by Technology Research Ltd. (United Kingdom) in 1984{{Cite news |date=March 1984 |title=Disk interface takes waiting out of wanting |url=https://worldofspectrum.org/archive/magazines/sinclair-user/24/0/1984/3/0#34 |work=Sinclair User |pages=34}} and released in 1985, with a price of £109.25 (or £249.75 with one disk drive).{{Cite news |date=January 1985 |title=More memory less labour |url=https://worldofspectrum.org/archive/magazines/pages/sinclair-user/34/73 |work=Sinclair User |pages=73}}

Beta 128 Disk Interface is a 1987{{Cite web |title=Beta 128 Disk Interface |url=https://spectrumcomputing.co.uk/entry/1000033 |access-date=2025-02-02 |website=Spectrum Computing - ZX Spectrum games, software and hardware}} version, supporting ZX Spectrum 128 machines (due to different access point addresses).

Beta Disk Interfaces were distributed with the TR-DOS operating system in ROM, also attributed to Technology Research Ltd.. The interface was based on the WD1793 chip.{{cite web |last=Extreme |first=Mac Buster |date=1999 |title=Tr-Dos v5.xx - programmer's manual |url=http://k1.dyndns.org/Vintage/Sinclair/82/Peripherials/Disc%20Interfaces/Beta%20128%20Disc%20Interface,%20TRDOS%20%28Technology%20Research%29/TRDOS/TR-DOS%20Programming.txt |url-status=dead |archiveurl=https://web.archive.org/web/20140409113112/http://k1.dyndns.org/Vintage/Sinclair/82/Peripherials/Disc%20Interfaces/Beta%20128%20Disc%20Interface%2C%20TRDOS%20%28Technology%20Research%29/TRDOS/TR-DOS%20Programming.txt |archivedate=2014-04-09 |accessdate=2013-12-16}} Latest firmware version is 5.03 (1986).

The Beta Disk Interface handles single- and double-sided, 40- or 80-track double-density floppy disks, and up to four drives.