BS ISO/IEC 7480:1991

Information technology. Telecommunications and information exchange between systems. Start-stop transmission signal quality at DTE/DCE interfaces. | Status: Confirmed, Current

1 Scope 1.1 This International Standard specifies signal quality requirements for serial data transmission at the interface between start-stop transmission Data Terminal Equipment (DTE) and Data Circuit-terminating Equipment (DCE). The interface referred to in this International Standard conforms to CCITT Recommendations V.24 (telephone networks) and X.24 (data networks) as specified in DCEs of the following CCITT Recommendations:

• - V.21, V.22, V.22 bis, V.23, V.26 ter, V.32, V.32 bis, X.20, X.20 bis together with V.28 electrical characteristics;
• - X.20 together with V.10 and/or V.11 electrical characteristics.

The signal quality requirement is limited to start-stop transmission at the interface with asynchronous DCEs, or with synchronous DCEs operating in asynchronous mode in accordance with CCITT Recommendations V.14 or V.42. Signal quality pertaining to DTEs working in a synchronous mode of operation is not part of this International Standard. This International Standard is also applicable when the interface as specified in the above CCITT Recommendations is provided at the ISDN Reference point R as defined in CCITT Recommendation I.411 and as specified in CCITT Recommendations V.110, V.120 and X.30.