ST language commands

The ST language commands are ending by a semicolon. The EOL character is treated in the same way as the space character.

CommandDescription Example
:= Assignment.\\
The value calculated on the right is assigned to the identifier on the left.
\\ A:=B; C:=SIN(X); My_FB(p1:=10, p2:=20);\\ 
Assignment.\\
Value of the variable declared on the left is assigned to the identifier on the right.
\\ FB1( out1 => my_var );\\ 
REF= Reference.\\
Variable on the left is filled with reference to the value on the right.
\\ MyVar:= 100; MyRef REF= MyVar; MyRef:= 200;\\ 
IF Selection command.\\
If the BOOLean condition is met the associated command is executed.
\\ IF A>10 THEN B:=1;\\ ELSE B:=2;\\ END_IF;\\ 
CASE Selection command.\\
Execution of a block of commands if the CASE condition is met.
\\ CASE TW OF\\  1,5: DISPLAY:=OVEN_TEMP;\\  2: DISPLAY:=MOTOR_SPEED;\\ ELSE DISPLAY:=STATUS;\\ END_CASE;\\ 
FOR Iterative command.\\
A loop of block of commands with an initial value, end condition, and increment value.\\
\\ FOR I:= 0 TO 10 BY 2\\ DO\\  J:=J+3;\\ END_FOR;\\ 
WHILE Iterative command.\\
A loop of block of commands with condition for exiting the loop at the beginning.
\\ WHILE J>10 DO\\ J:=J+2;\\ END_WHILE;\\ 
REPEAT Iterative command.\\
A loop of block of commands with condition for exiting the loop at the end.
\\ REPEAT\\ J:=J+2;\\ UNTIL J>10;\\ 
EXIT Exiting the loop.\\
Premature exiting of the command loop.
\\ EXIT;\\ 
RETURN Return.\\
Leaving of the currently executed block.
\\ RETURN;\\ 
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