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User-to-Host Transmission

Keyboard is the set of input devices at the user's console. Input bits from stations, after drifting through levels of monitor and interrupt handlers, eventually come to the encode translator. [>nif(encode)]

Encode maps the semi-raw input bits into an input stream in a form suited to the serving-host subsystem which will process the input. [>nif(hrt)<nif(keyboard)]

  • The Encode program was supplied by the server-host subsystem when the subsystem was first requested. It is sent to the user machine in symbolic form and is compiled at the user machine into code particularly suited to that machine.

  • It may pack to break characters, map multiple characters to single characters and vice versa, do character translation, and give immediate feedback to the user.

  • 1 dm: Immediate feedback from the encode translator first goes to local display management, where it is mapped from the NET standard to the local display hardware.

  • A wide range of echo output may come from the encode translator. Simple character echoes would be a minimum, while command and machine-state feedback will be common.

  • It is reasonable to expect control and feedback functions not even done at the server-host user stations to be done in local display control. For example, people with high-speed displays may want to selectively clear curves on a Culler display, a function which is impossible on a storage tube.

Output from the encode translator for the server-host goes to the invisible IMP, is broken into appropriate sizes and labeled by the encode translator, and then goes to the NET-to-host translator.

  • Output from the user may be more than on-line input. It may be larger items such as computer-generated data, or files generated and used exclusively at the server-host site but stored at the user-host site.

  • Information of this kind may avoid translation, if it is already in server-host format, or it may undergo yet another kind of translation if it is a block of data.

  • hrp: It finally gets to the host, and must then go through the host reception program. This maps and reorders the standard transmission-style packets of bits sent by the encode programs into messages acceptable to the host. This program may well be part of the monitor of the host machine. [>tif(net mode)<nif(code)]