The ARRB cassette reading station, version i
Koen Vos · 1982
The cassette reading station (crs) is an application of ARRB's modular microprocessor based data acquisition system (ambdas). The station facilitates the retrieval of data recorded on digital data cassettes as specified by the American national standards institute. Only the reading function is provided, there is no writing facility. The crs interfaces to a computer compatible terminal device (printer or visual display unit) and to a host computer system, via identical, but separate, serial asynchronous links. Both links use the Electronic Industries Association rs232-c protocol. Data read from the cassette, or, data entered from the terminal keyboard may be directed to either the display device or to the host computer. Data from the computer may be directed to the terminal display. A maximum cassette data reading rate of 500 characters per second is attained by the crs. This rate is achieved with a tape velocity of approximately 250 mm per second and a block size of 86 characters. Manual control of the cassette mechanism (replay start/ stop, fast forward, rewind, loading, etc) is via switches located on a module of the crs. Remote control of replay start/ stop by the host computer is provided, and is useful in situations where the host computer is incapable of accepting data continuously. System status messages are directed to the terminal device. Errors encountered during replay of cassette data generate messages that may be displayed on the terminal device, or alternatively, may be directed to the host system. Operator selectable options are provided to modify the operation of the remote replay control and the reporting of replay errors (a).