PLCSIM stops with load instruction with AR1

Dear friends

I've strange problem with PLCSIM when testing program with both TIA14 and STEP-7 V5.6 that I use the following simple code:

L P#2.0

LAR1

L IW[AR1, P#2.0]

T QW[AR1, P#10.0]

just downloading code the CPU (Of PLCSIM stops) even when using binary as follows it works good

L P#2.0

LAR1

A I[AR1, P#2.0]

= Q[AR1, P#10.0]

I don't know why??

please i need answer

Hi Hassan

L P#2.0

LAR1

L IW [AR1, P#2.0]

T QW [AR1, P#10.0]

your above code will (and must) execute correctly and does so when run in my PLCSIM as per attached pic.

You will though get "alignment errors" that you are seeing in your diag buffer if you have a bit address <> 0 during BYTE, WORD or DWORD access.

In other words, any of the examples below will cause alignment errors so please check your actual code again to see if this is the case:

L P#2.1  // bit number <> 0 --> alignment error with word access below

LAR1

L IW [AR1, P#2.0]

L P#2.0

LAR1

L IW [AR1, P#2.3] // bit number <> 0 --> alignment error with word access 

Dear Fritz

Thanks I get it

when using word addressing we set initial bit address to 0 (as L P#10.0]

but when we use bit addressing it is OK to set either 0 or any value and it works with me.

thanks again