Question on G-code Comments

[trottrr50]

I have been working with ‘g-code comments’ using the convention in the centroid m-series operators manual that uses “colons” and “semicolons” to denote comments in a g-code program. Both the Peter Smid CNC programming Handbook and Machinery’s Handbook (page 1229) indicate the usage of Parentheses before and after the comment. I thought that use of parentheses for comments was an industry standard. Why is the method used by Centroid different.

steve

[cnckeith]

you can user either..no problem.
";"
or "(" they both work as comment indicators to cnc12

[wilkin250r]

I’ve seen brands that use brackets [comment]

[cnckeith]

yeah don't use brackets you'll get an "invalid character" message from cnc12. if you have a g code program that has brackets.. edit it and do a search and replace. I use Notepad++ as a G code editor... here is how to use Notepad++ as a g code editor. http://www.centroidcnc.com/dealersuppor ... ds/294.pdf

[cncsnw]

... but parentheses (which are called 'brackets' in some parts of the world) are perfectly fine for comments on a Centroid control.

Actually, there is one obscure exception: in a variable assignment, where the right-hand side can optionally contain an arithmetic expression, you cannot use parentheses for comments. There you should use the semi-colon instead.

#101 = 3.14159 (this is an error)
#102 = 2.71828 ; but this works fine

[tblough]

(Parentheses)
[Brackets]
{Braces}

What are these called in other parts of the world?