IBM remote batch terminals
The IBM 2780 and the IBM 3780 are devices developed by IBM to perform remote job entry (RJE) functions; they communicate with the mainframe via Binary Synchronous Communications (BSC or Bisync) and replaced older terminals using Synchronous transmit-receive (STR). In addition, IBM has developed workstation programs for the 1130, 360/20, 2922, System/360 other than 360/20, System/370 and System/3. 2780 Data Transmission Terminals. The 2780 Data Transmission Terminal first shipped in 1967. It consists of: The 2780 is capable of local (offline) card to print operation. It comes in four models: The 2780 uses a dedicated  communication line at speeds of 1200, 2000, 2400 or 4800 bits per second. It is a half duplex device, although full duplex lines can be used with some increase in throughput. It can communicate in "Transcode" (a 6-bit code), 8-bit "EBCDIC", or 7-bit "ASCII". 3780 Data Communications Terminal. In May 1972, IBM announced the IBM 3780, an enhanced version of the 2780. The 3780 was developed by IBM's Data Processing Division (DPD). There is one model, with an optional card punch. The 3780 drops Transcode support and incorporates several performance enhancements. It supports compression of blank  fields in data using run-length encoding. It provides the ability to interleave data between devices, introduces double buffering, and adds support for the Wait-before-transmit ACKnowledgement (WACK) and Temporary Text Delay (TTD) Binary Synchronous control characters. The IBM 2780 and 3780 were later emulated on various types of equipment, including eventually the personal computer. A notable early emulation was the DN60, by Digital Equipment Corporation in the late 1970s. 2770 Data Communication System. The 2770, announced in 1969, ""was said to surpass all other IBM terminals in the variety of available input-output devices."" The 2770 was developed  by the IBM General Products Division (GPD) in Rochester, MN. It comes standard with a desktop terminal with keyboard. The printer and other devices (any two in any combination) can be attached to the 2772 Multi-Purpose Control unit. Possible devices include: 3770 Data Communications System. In 1974 IBM Data Processing Division (DPD) offered a successor, called the 3770 Data Communications System, that supports SDLC, BSC, BSC Multi-leaving and SNA, depending on the configuration. The 3770 is a family of desk console style terminals that offers a variety of keyboard and printer combinations as well as I/O equipment  attachment and communications features. The terminals come built into a desk and include the following models: The following I/O devices can be attached to a 3770 terminal: Workstation programs. IBM distributes workstation programs with systems software including Except for the RJE workstation programs in OS/360, these programs use a variation of BSC known as Multi-leaving. In addition, IBM provides separately ordered workstation programs using BSC. Systems Network Architecture (SNA) and TCP/IP. Workstation programs are available from IBM and third-party vendors to support all of these protocols: