Synchronous interface between data terminal equipment and data circuit - terminating equipment employing serial binary data interchange 使用串行二进制数据交换的数据终端设备和数据电路端接设备间的同步接口
2.
Simple 8 - position non - synchronous interface between data terminal equipment and data circuit - terminating equipment employing serial data interchange 利用串行数据互换的数据终端设备和数据电路终接设备间的单一8位非同步接口