The variable define question???

2020-02-27T20:51:45.740000Z

Thank you for your explain!!

The variable define question???

2020-02-27T20:51:41.606000Z

This is the so called VAR_CONFIG.

The idea is that you can define FB with I/O access. If you do that in the standard way

VAR
STATE AT %IX0.0: BYTE;
...
END_VAR

you will not be able to use instances of FBs with different I/Os, because the access to the process image is fixed.

With the VAR_CONFIGs you can leave the implementation of the acccess to the I/Os open to the instances. In the object "Variable_configuration" under the register card "Resources" in the folder "Global Variables" you can the terminate, which instance should use which I/O.

Example:
You define an FB with your declarations.
You declare two instances of the FB (Inst1, Inst2)
* You terminate which I/Os the instances should access to: Open the "Variable_configuration", mark everything (including the VAR_CONFIG/ END_VAR), call the command under "Insert/All instance Paths" ==>

VAR_CONFIG
   PLC_PRG.inst1.STATE AT %I : BYTE;
   PLC_PRG.inst1.DATAIN AT %I : WORD;
   PLC_PRG.inst1.CTRL AT %Q : BYTE;
   PLC_PRG.inst1.DATAOUT AT %Q : WORD;
   PLC_PRG.inst2.STATE AT %I : BYTE;
   PLC_PRG.inst2.DATAIN AT %I : WORD;
   PLC_PRG.inst2.CTRL AT %Q : BYTE;
   PLC_PRG.inst2.DATAOUT AT %Q : WORD;
END_VAR

Now you can write the specific address in it. E.g.

VAR_CONFIG
   PLC_PRG.inst1.STATE AT %IB0 : BYTE;
   PLC_PRG.inst1.DATAIN AT %IW10 : WORD;
   PLC_PRG.inst1.CTRL AT %QB0 : BYTE;
   PLC_PRG.inst1.DATAOUT AT %QW10 : WORD;
   PLC_PRG.inst2.STATE AT %I B1: BYTE;
   PLC_PRG.inst2.DATAIN AT %IW11 : WORD;
   PLC_PRG.inst2.CTRL AT %QB1 : BYTE;
   PLC_PRG.inst2.DATAOUT AT %QW11 : WORD;
END_VAR

I hope this will explain you the function

The variable define question???

2020-02-27T20:51:40.221000Z

Hello all:
I had see a example ,the variable define like:
VAR
STATE AT %I: BYTE;
DATAIN AT %I: WORD;
CTRL AT %Q: BYTE;
DATAOUT AT %Q: WORD;
END_VAR

My question is "%I*" ???What is it mean???

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