1) Control character
Found on
https://www.crosswordclues.com/clue/bell-character
A bell code (sometimes bell character) is a device control code originally sent to ring a small electromechanical bell on tickers and other teleprinters and teletypewriters to alert operators at the other end of the line, often of an incoming message. Though tickers punched the bell codes into their tapes, printers generally do not print a charact...
Found on
http://en.wikipedia.org/wiki/Bell_character
No exact match found.
