Display control 4. Command sequences After switching the system on every character that is transmit- ted to the terminal is displayed on the screen. An exception are special characters which either represent a command or intro- duce one. In the latter case, the introducer is followed by further characters which specify the command in more detail. There are no more characters put out to the screen until all characters of a complete command have been received by the terminal. Reception of unknown characters If, within a command sequence, a character is received that does not belong to the command the command recognition is aborted and the sign "ї" is displayed on the screen.
KDT 635 and KDT 633 are programmed by using command sequences which follow the common standards of well-known terminal manufacturers. Each command sequence is given in its hexadecimal, decimal, and ASCII codings. The following examples may serve as an explanation: Hexadecimal Coding : (Hex) ODh: hexadecimal notation of the ASCII character CR (Car- riage Return). The “h” signifies hexadecimal notation. For the transfer of ODh to the terminal only one charac- ter (i.e. ASCII character CR) is transferred to the termi- nal. Decimal Coding: 13: decimal notation of the ASCII character CR. ASCII-Coding: CR: ASCII notation of Carriage Return (cf. appendix "B.1. ASCII table"). 4 - 1