Hexadecimal code

When a dollar sign ($) is in a string literal, the following two characters are interpreted as a hexadecimal code according to the coding in ISO/IEC 8859-1. The code also corresponds to ASCII code. In addition, note the special cases and control characters.

Table 543: Hexadecimal code
String with $ Code	Interpretation
`‎'$<8-bit code>'‎`	8-bit code: Two-digit hexadecimal number that is interpreted according to ISO/IEC 8859-1
`‎'$41'‎`	`‎A‎`
`‎'$A9'‎`	`‎©‎`
`‎'$40'‎`	`‎@‎`
`‎'$0D'‎`	Control character: Line break (corresponds to '$R')
`‎'$0A'‎`	Control character: New line (corresponds to '$L' and '$N')

Table 544: Special cases
String with $ code	Interpretation
`‎'$L'‎`, `‎' $l'‎`	Control character: Line feed (corresponds to `‎'$0A'‎`)
`‎'$N'‎`, `‎'$n'‎`	Control character: New line (corresponds to `‎'$0A'‎`)
`‎'$P'‎`, `‎'$p'‎`	Control character: Form feed
`‎'$R'‎`, `‎'$r'‎`	Control character: Line break (corresponds to `‎'$0D'‎`)
`‎'$T'‎`, `‎'$t'‎`	Control character: Tab
`‎'$$'‎`	Dollar sign: `‎§‎`
`‎'$''‎`	Single straight quotation mark: `‎'‎`

Constant declaration

VAR CONSTANT
        constA : STRING := 'Hello Allgäu';
        constB : STRING := 'Hello Allgäu $21'; // Hello Allgaeu!
END_VAR