Hi, problem with DB data...

[userxyz]

I have a strange problem,

As you can see, the Latchvalues are identical, this is basically unpossible...

When I connect first to MD10, MD20, MD30 and MD40 (refer to network 3) and then to the DB data, then everything works like it should...

But not if I use the DB Data like you can see on the image ???

How is this possible ?

 

[userxyz]

If I write first to temps, then it works ???

If I first write to temps, then it works ????

 

[L D[AR2P#0.0]]

From your previous post, #LATCH is only written to under certain conditions. If this is so, the #LATCH will need to be an IN_OUT type variable - my guess is it's an OUT which is why it fails when using a fully defined DB address as the parameter. Then again with the little detailed information provided, I may be wrong.

 

[L D[AR2P#0.0]]

Combo - any feedback from my suggestion ?

 

[userxyz]

I'll test it today my dear,

Thanks btw, kiss :-o

 

[userxyz]

amazing

Okay,

First of all, you are amazing dude...

It was indeed an OUT, and indeed I write to it under certain conditions. I made an IN/OUT from it, like you said, and it works now...


So, when u jump over the variable, and you don't write to this OUT variable where a DB value is connected to on the outside of the function, then troubles come along... ?

With an FB I wouldn't had this problem I suppose ?

From your previous post, #LATCH is only written to under certain conditions. If this is so, the #LATCH will need to be an IN_OUT type variable - my guess is it's an OUT which is why it fails when using a fully defined DB address as the parameter. Then again with the little detailed information provided, I may be wrong.

 

[L D[AR2P#0.0]]

Yes, you are correct about the FB case. If you want more explanation about what is going on, read through the following thread. The original question was about the differences between Step5/7 but it develops into the mechanism used for FC parameters.

http://www.plctalk.net/qanda/showthread.php?t=29559&highlight=fully+defined

 

[userxyz]

k

In that Thread, Sparkz says it would be better to make everything IN/OUT... in an FC, it's much safer...

Is that correct ?

Yes, you are correct about the FB case. If you want more explanation about what is going on, read through the following thread. The original question was about the differences between Step5/7 but it develops into the mechanism used for FC parameters.

http://www.plctalk.net/qanda/showthread.php?t=29559&highlight=fully+defined

 

[L D[AR2P#0.0]]

In that Thread, Sparkz says it would be better to make everything IN/OUT... in an FC, it's much safer...

Is that correct ?

I use OUT if I'm always writing the output
I use IN/OUT if I conditionally write the output or use the variable for incrementing etc.

You could use IN/OUT all the time but note there may be extra code/processing where it may not be required.

 

[10BaseT.]

What was it you said about neat code with lots of comments....?

 

[userxyz]

...

Euhm, first coding, then comments

What was it you said about neat code with lots of comments....?