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[L D[AR2P#0.0]]

All variables in the temp area are not initialised or remembered between calls. You are using TEMP0 as if it is.

 

[clemens]

This is not a big issue as far as getting this FC1060 to work. The issue is WHY does it not work. So if I know why this is not allowed I can apply that information to other situations.

I tried lots of different combinations, IN_OUT, STAT, etc.

It seems to me like it should at least work in a FB with a DB assigned.

SO maybe I have some other issue all together, I don't know.

The program you sent in the picture does not work because you are using a temporal variable to be decremented. This variable is initialized each time you proces the function. Instead of TEMP0 you should use an IN/OUT variable, because you are reading and writing values in it, like in the pictures I'm sending.

 

[PeterW]

The program you sent in the picture does not work because you are using a temporal variable to be decremented. This variable is initialized each time you proces the function.

Just a small correction, the temps are not initialised each time you process the function.

The memory area that the temp used is a scratch flag area, so other functions may have used it, the fact is a temp BOOL for instance can be 'ON' or 'OFF' at the start of a block, it's start state may change from scan to scan depending on if it was used elsewhere.

Its condition in indeterminable at the start of the block call.

 

[clemens]

You are completely right. What I was trying to tell is that you can't expect a value you stored in one cycle to be there the next cycle.

 

[dahnuguy]

just updating an old thread, skip it if it bugs you

Why have you used a function block (FB) as opposed to a function (FC) ?

I now understand your question and just bumped into this thread again.

I used an FB because I stored all the current and previous levels in the instance DB.

I know some people who use an FC with a DB to store variables and they think that is better than using a FB with instance DB.

I like using a FB, it generates the DB for you and there are several neat ways to use the instance DB in the code.

And FBs allow ANY pointers as inputs and some inputs work differently or not at all in FCs.

I understand why now, but back then it was all very irritating.

 

[Lancie1]

It just goes to prove what my old mother told me: "A guy can learn a lot in 3 years".

 

[dahnuguy]

It just goes to prove what my old mother told me: "A guy can learn a lot in 3 years".

you have no idea