Step 7 Blockmoves

I work for a systems integrator and I am very famliar with Modicon, GE, and Allen Bradley. I know function block programming and ladder. All of the above packages have a means to "Move/Copy" internal bits to other locations, whether it is to another bit memory location or to word memory.

For instance
Moving 16 bits from %I1 ---> %R1
Moving I:0/1 ----> N7:10

I have been given my first project in Siemens Step 7. I never use the literal digital input addresses (I 1.0) in the program. This is so i can break the copy link (I 1.0 --- M 1.0) for desktop simulations of the program before install.

My question is how do you do this in Ladder? I do see the Blockmov SFC21 in the list. I try to call it using ---(Call). And this doesn't work. Is there a simple instruction that will move a variable length blocks of bits to another bit location (M 1.x) or to work locations (MW 1)?

Thanks for the help.

Drag SFC20 block from the list onto your line of ladder - you will then see that you have to supply parameters. Here are the three steps:



SFC20 allows you to specify any number of bits. You may want to use the move command which will allow you to move 8, 16 or 32 bits at a time.

Thanks Alot.
Once i saw your screenshots and you weren't pulling my leg cause i had to of tried to drag that block onto my ladder at least a dozen times I went searching for some other SFC20/21 to drag.

So apparently my problem is, and maybe someone can explain why, that I cannot drag the SFC's from the tree folder "stdlibs" but it will drag from "Standard Library". Doesn't make a bit of sense to me but I'm the noob.

Thanks for the help

I believe stdlibs is a legacy library for very early versions of Step 7 - that's why it will not drag.