Principle of teletypewriter

Teletypewriter to start and stop work, usually using five units of code, that is, the international number 2 code. It is the use of five equal-length pulses of "yes", "no" of the 32 combinations of representative characters (letters, numbers, punctuation), plus the start pulse and stop pulse transmission. Some teletype machines use seven-unit code, that is, the international number 5 code. It is 128 kinds of combinations on behalf of a variety of characters and control information, can be adapted to a wide range of requirements. The notification rate of mechanical telex machine is usually 50, 75, 100 baud (five-unit code) and 110 baud (seven-unit code). Electronic teleprinter notification rate of up to 300 baud.