CONTROL CODES

NUL null character, filler DLE data line exchange

SOH start of header DC1 device control 1, Xon

STX start of text DC2 device control 2

ETX end of text DC3 device control 3, Xoff

EOT end of transmission DC4 device control4

ENQ enquiry NAK negative acknowledge

ACK acknowledge SYN synchronisation

BEL bell ETB end of transmission block

BS backspace CAN cancel

HT horizontal tab EM end of message

LF line feed SUB substitute

VT vertical tab ESC escape

FF form feed FS frame separator

CR carriage return GS group separator

SO shift out RS record separator

SI shift in US unit separator

DEL delete