During the late 1960 and 1970s, the computing environment expanded beyond the large computer rooms based on card input/output and started to allow data input and output terminals from remote locations. For such purposes, printer terminals such as the
IBM 2741, using the traditional
asynchronous serial communication (start-stop signaling), and display terminals such as
IBM 2260 and
IBM 3270, using the new communications protocol set (
Binary Synchronous Communications or BSC), became available. There were needs to use a new more efficient communications protocol set and to make available a more efficient and reliable remote printer and display terminals. To satisfy such needs, IBM 3767 serial printer and
IBM 3770 communications system (including a line printer) became available as part of the "
Advanced Communications Function" (ACF) announcement which included the new
System Network Architecture (SNA) and Synchronous Data Link Control (SDLC) communications protocol set, followed by another announcement in July, 1975, which included IBM 3760 Data Entry Station and the new models of
IBM 3270 display stations, and
IBM 3790 communication system. ==3767 functions, features and models==