Siemens SINUMERIK 840DE Programming Manual page 65

Note
Labels must be unique within a program.
Labels always appear at the start of a block. If a program number exists, the label appears
immediately after the block number.
Comments
To make NC programs easier to understand for other users and programmers, it is advisable
to insert meaningful comments in the program.
Comments are appended to the end of a block and are separated from the program section
of the NC block by a semicolon (";").
Examples of comments
N10 G1 F100 X10 Y20
Or
N10
N20
N50
Note
Comments are stored and appear in the current block display when the program is running.
Programming messages
Messages can be programmed to provide the user with information about the current
machining situation during program execution.
A message in an NC program is generated when the message text is typed after vocabulary
word "MSG" in round parentheses "()" and double quotation marks.
A message can be deleted using "MSG ()".
Example of activating/deleting messages
N10 MSG ("Roughing the contour")
N20 X... Y...
N ...
N90 MSG ()
Fundamentals
Programming Manual, 10.2004 Edition, 6FC5 298-7AB00-0BP1
Fundamental Principles of NC Programming
2.2 Language elements of the programming language
;Comments to explain the NC block
;Company G&S, order no. 12A71
;Program written by H. Müller, Dept. TV 4
;on November 21, 1994
;Section no. 12, housing for submersible pump type
TP23A
;Activate message
;Clear message from N10
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