840 标准查询与下载

DS/ISO 4903:1981 信息技术.数据通信.15路数据终端设备/数据通信设备(DCT/DCE)接口连接件和触点数分配

This International Standard specifies the 15-pin connector and the assignment of connector pin numbers at the interface between data terminal equipment (DTE) and data circuit-terminating equipment (DCE) where CCITT1) Recommenda-tions X.24, X.26, and X.27 are applicable.

Data communication. 15-pin DTE/DCE interface connector and pin assignments

DS/ISO 2110:1981 数据通信.25插脚数据终端设备/ 数据线路终端设备(DTE/DCE )的接口连接件和插脚分配

This International Standard specifies the 25-pin connector and the assignment of connector pin numbers at the interface between data terminal equipment (DTE) and data circuitterminating equipment (DCE) or automatic calling equipment (ACE). It is applicable to voice band modems, public data network (PND) facilities, telegraph signal converters, and automatic calling equipment where CCITT1) Recommenda-tions V.24 and V.28 are applicable. In the case of the PDN attachment through the X.20 interface, the functions of the interchange circuits are in accordance with CCITT Recommendation X.24. In the case of the V.20 type outstation interface, the electrical characteristics are in accordance with CCITT Recommenda-tion V.31.

Data communication. 25-pin DTE/DCE interface connector and pin assignments

DS/ISO 1113:1979 信息处理.穿孔纸带的7位编码字符集表示法

This International Standard specifies the representation of the 7-bit coded character set on punched tape 25,4 mm (1 in) wide.

Information processing. Representation of the 7-bit coded character set on punched tape