What does the “@” sign mean (Omron PLC)?

[jamesrustin]

What does the "@" sign means in ladder programming? Documentation explains the @ specifies an indirect DM address in binary mode ... offset an memory area: what does that mean actually?

 

[BobB]

The @ sign in a function means operates only on a leading edge.
For example, With the older PLCs @INC or with the newer PLCs @++ means increment a channel by 1 on a leading edge. The ++ function in the newer PLCs is binary while the INC function in the older PLCs is BCD.
Makes life easy as I can enter the whole lot from the keyboard - no ruddy drag and drop nonsense or fiddling around with horrid FBs!

 

[TurpoUrpo]

Omron FB's indeed are pretty horrid.

 

[BobB]

I have yet to find FBs that are not pretty horrid - includes Siemens, Omron, Schneider - have not been forced into FBs in AB yet so no comment.

 

[paraffin power]

Omron FB's indeed are pretty horrid.

I think they're handled brilliantly.

Regarding the '@', bob is right when placed in front of an instruction, but in the context that the op asked about, it is (one of) Omron's ways of indirect addressing.
If d10 contained 20, then @d10 would address d20. Index registers are a little more involved, but much more functional.
Pp

 

[TurpoUrpo]

I have yet to find FBs that are not pretty horrid - includes Siemens, Omron, Schneider - have not been forced into FBs in AB yet so no comment.

Siemens FB's are pretty fine, CoDeSys has better implementation. But omron ones are horrid.

 

[DamianInRochester]

The use of the @ in function blocks for Omron is my favorite feature of the software. I wish everyone else had this feature as well. The extensive ability to assign hotkeys and save those profiles is also second to none that I have seen. Referencing the instructions with a 3 letter mneumonic is also nice for quick coding and not having to reach for the mouse to often.

 

[BobB]

The extensive ability to assign hotkeys and save those profiles is also second to none that I have seen.

Yes it is really good - saves heaps of time. I have had to change my shortcuts because of the shortcuts Dell have built into their laptops - they clashed with my shortcut allocations for CX-Programmer.

Referencing the instructions with a 3 letter mneumonic is also nice for quick coding and not having to reach for the mouse to often.

Really good too - and the ability to just type a full instruction string in the pop up box - also the ability to just type in an I/O number without having to fiddle about with symbol programming - old guy and brought up that way - dislike symbol programming - too tedious - prefer numbers and the keyboard.

 

[TurpoUrpo]

I do agree that in many ways omron is superior to use. Only that their programming, hmm. lets say philosophy does not suit me. German one suits me better