MOV function in CX-programer

I'm studying a Ladder program, but I don't understand How different between @MOV(21) function and MOV(21) function. Could anyone let me know, please? Thanks in advance.

In Omron CX-Programmer you can use the @ symbol in front of some operands to turn them into a 1-shot

The @MOV (or any instruction with an @ in front) will execute ONCE per false-to-true transition of the input condition(s).

Example LD 0001 MOV 113 DM100 will constantly - every scan - copy the contents of address 113 to address DM100, until the input 001 goes off.

What you will get in DM100 is the value that was in 113 _just_ before the input went off.

Eg: with MOV
scan # - IN0001 - 113 - DM100
1 off 10 0 (or last saved value)
2 on 20 20
3 on 30 30
4 off 40 30

Eg: with @MOV
scan # - IN0001 - 113 - DM100
1 off 10 0 (or last saved value)
2 on 20 20
3 on 30 20
4 off 40 20

Hope it helps!

RT

Wooh thank RoTaTech very much, your answer is so detail, now I have understood their feature. I will not have to think a lot for them anymore

Instruction Variation and Timing

This subject is thoroughly covered in the OMRON PLC manuals.
See attached extract from W451-E1-03 CP1H CP1L Programming Manual.