AN    Flag2
JC   AUTO

JC is a conditional jump.

So: if Flag2=0 then goto label AUTO

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Split from Should STL be retired?.

Robert49

AN    Flag2
JC   AUTO

JC is a conditional jump.

So: if Flag2=0 then goto label AUTO

This is not correct and that is the trap of STL

It depends what the RLO was at the beginning, and if this is not managed, the program will not work as expected:

From the STL manual:

AN And Not
Format N <Bit>
Address Data type Memory area
<Bit> BOOL I, Q, M, L, D, T, C
Description
AN checks whether the state of the addressed bit is "0", and ANDs the test result with the RLO.

Brian

Hi,

The RLO is always 1 at the beginning. If u write some logic before given logic then definately RLO will get modified.

STL is most effective, proven so I don't find any problem with it.