GB1320895A - Data storage systems - Google Patents

Abstract

1320895 Telephone keyset systems POST OFFICE 30 June 1970 [2 July 1969] 33501/69 Heading H4K Communication with a data storage system which is accessible over a telephone exchange, is conducted with a pushbutton keyset each pushbutton of which has a multiple significance according to how long it is held operated. The keyset is of a standard sort used to establish connections over an exchange system. A remote computer automatically responds to a call and returns a ready-to-proceed signal. The computer evaluates the signals received according to their intrinsic content as a tone or combination of tones, or as D.C. signals, and according to the length of time each signal persists. While the keys have their customary numerical significance if operated for a short period, such as less than half a second, a longer period of operation may give the keys a second significance such as to indicate operations of addition, multiplication and so forth, or to represent letters of the alphabet. The second significance of the keys can be set out on a template placed temporarily over the keyset or may be carried by the buttons. While an operator can be relied upon to judge the difference between short and long intervals to establish two levels of significance for the keyset, further levels of time discrimination requires the delivery of timing signals from the computer, such signals being a sequence of tones or a sequence of verbal responses identifying the interpretation put upon each key signal as the various intervals of time elapse, the operator releasing a key when the desired significance is notified.