Device comments

[tvaughn 0]

Hello, Our company uses Mitsubishi exclusively mostly FX2n and A1SH plc's programmed with GX developer software. It is a company standard that device comments not be stored in the plc according to the head engineer it slows down the processor. I did not think this was true, but can't find anything documented to prove him wrong. Is there any truth to this? If so how much does it slow it down? Thanks in advance.

[panic mode 246]

I don't see why this would slow down the plc but is sure takes memory away... Edited 17 Aug 2003 by panic mode

[navillusi 2]

Comments are stored in a different memory location, away from the program code. The comment area of the memory is only accessed when you read it out with GX Developer, not during normal program scans, thus it will not slow the processor down

[Guest Guest]

What some people in charge of others think eh!!!! I am the boss so all I say is gospel - met em all. The plc has no interest in the comments, when downloading a program it is compiled into machine code and then only the instructions are scanned. Mitsibushi are one of only a very few that actually allow you to use spare memory for comments. (with the right software) and it is sometimes a godsend. In this day of ultra cheap memory why arnt more doing it. I have said for years that 4MB of mem in a plc could be used to save documents - cad drawings and anything pertaining to the program so that years from now - when the machine has been sold 3 times - the poor sap that inherits it has all the documentation he could wish for.

[panic mode 246]

amen