ICOMR

Hi, 

I have to transfer the inputs & outputs to an DB. The probleme comes when I try to LOAD bit by bit (LIST language) , TIA Portal said thats is not possible cause (textually): "The bit is not authorised for this instruction" (see picture).

Why in CONT langage works? (see picture)

Do you have any methode more easy or performance to put all my inputs and outputs directly in my DB (in the good address)?.

My supervision HMI  has to conect with the DB.

 Hi .. welcome!

What you ask is done as follows.

A "startButton"  // bit AND used to load the bit
= "myDB".copy_startButton //This is the DB

 But doing one-by-one is not needed.
You can do this as a group.

L %ID0   //absolute inputs read as double word
T %DB1.DBD0 //transfer to absolute DB address

 Other variations are also possible.

Helpful?
w

ICOMR

Hi,

Thanks for you answer, but the problem is still there.  I did the first solution and no problems (see photo 1). The problem is that I have many Inputs & Outputs (digitals & Analogics) , so that is a lot of work to write bit by bit.

The second solution seems more performant but I have only BITS (not double words).
Besides that, when I try to simulate and force my variables (to see if my db is updated), nothing happens in the simulation, see two photo 2.

Thanks for your help, I'm new in TIA PORTAL

Hi.

I see from the photo the LAD (Ladder code) you marked that the power line does not turn on (green). Possibly you have not called the FB / FC in OB1.

OB code blocks will run with special triggers (every cycle / interrupt / regular times). Other code blocks (FC / FB) must be called somewhere.

Next...
The inputs and outputs have addresses like I1.0. That means bit 0 of byte 1. That means that I1.0 is one bit element inside IB1.

Also you have BYTE being part of a WORD and WORD part of a DWORD.

In our example you will find I1.0 in IB1 ... IW0 ... ID0.

When defining bits in a DB, these bits have addresses also (exceptions for S7-1200 and S7-1500)

The bit of the DB you used in the code has an address: DB120.DBX0.0. This is also part of a bigger grouping.. even if you did not specify it by name. DB120.DBB0 is for example the BYTE where the bit is from.

Does this make sense?
w

ICOMR

Thanks again,

Very hepfull your suggests...

When I put my FB Inside of OB1, do I have to fill the FB1 with all my inputs???. It's not enough to just load the block?

Thanks very much

Hi.

No you can have direct addressing inside FB1,
you do not need to create parameters for each input.

Still having problems with the code inside FB1 not working?
Consider to make a small program and ZIP it.
Then you can add it in the forum.

w