Guide to This Manual

Chapter 1 “Introduction” introduces Asynchronous Serial Communications (ASC) and the organization of the hardware and software used by the Distributed Terminal Subsystem (DTS). Includes a review of basic data communications concepts relevant to asynchronous devices connected to HP 3000 Series 900 computer systems.

Chapter 2 “Controlling Asynchronous Devices Programmatically” summarizes the programmatic control of asynchronous devices. Provides an overview of the file system and device operation, along with a general description of using intrinsics in a program.

Chapter 3 “Common Device Control Functions” contains additional information needed to use intrinsics successfully in a user program, and provides code samples to demonstrate how intrinsics can be used to perform some basic device control functions.

Chapter 4 “Using FDEVICECONTROL” provides information on how the FDEVICECONTROL intrinsic may be used to perform terminal control functions. Code fragments demonstrate several of the functions performed by this intrinsic.

Chapter 5 “Using Subsystem Break” explains the use of subsystem break and summarizes the intrinsics involved. Includes example code illustrating a subsystem break handler and a procedure to enable subsystem break.

Chapter 6 “Typeahead Mode” describes the programmatic controls involved in the use of typeahead mode. Code fragments illustrate the use of these controls.

Chapter 7 “Programming for PAD, DTC Telnet, Telnet/iX Server, and VT Devices” describes how PAD and DTC Telnet connections are implemented through DTCs. For PAD connection, a DTC must be equipped with a DTC/X.25 Network Access Card, and for DTC Telnet connections a DTC must be equipped with a Telnet Access Card. Both pieces of hardware require the appropriate OV DTC Manager network management software. This chapter explains differences involved with the programmatic control of these devices. This chapter also describes how connections are implemented via the Telnet/iX Server and via Virtual Terminal (VT) services.

Chapter 8 “Intrinsics Reference” contains a detailed description of the MPE/iX Native Mode intrinsics that are most useful for the programmatic control of asynchronous devices. Describes the syntax, parameters, and condition codes or status return for each. When applicable, functional returns, special considerations, and references to additional sources of information are included.

Appendix A “Comparing MPE/iX Systems to MPE V Systems” provides a comparison between asynchronous devices connected to an MPE V system and those connected to an MPE/iX system.