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About szlaur.jakub

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    Hi, I am New!

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  1. I am trying to create a simple `Hello World` Modbus TCP/IP program using Twincat3 and virtual PLC (PLC running locally on my computer).   I have set up a LabVIEW Modbus TCP/IP master + slave program (both of which are working see screenshots below).  I can send data between LabVIEW's master and slave programs. And also read the data from Python script (so I know for sure they are all working).  Now I have tried to create a Twincat3 program to set some registers using Beckhoff example What I have tried:  - I have tried changing the ipAddr parameter to: 'localhost', '', ''  - Also I have tried the nUnitID set to: 0, 1, 16#FF (16#FF as specified by Beckhoff docs) This is my Beckhoff code:     PROGRAM MAIN     VAR         ipAddr         : STRING(15) := ''; //Tried also and 'localhost'         M0 AT %MB0     : ARRAY [0..3] OF WORD;         nValue         : ARRAY [0..3] OF WORD;         fbWriteRegs : FB_MBWriteRegs;         bWriteRegs     : BOOL;     END_VAR           IF NOT bWriteRegs THEN         nValue[0]                := nValue[0]+1;         nValue[1]                := nValue[1]+1;         nValue[2]                := nValue[2]+1;         nValue[3]                := nValue[3]+1;                  bWriteRegs                 := TRUE;                  fbWriteRegs.sIPAddr     := ipAddr;         fbWriteRegs.nTCPPort     := 502;         fbWriteRegs.nUnitID        := 16#FF;             //Tried setting this to 0,1 and it also and didnt work ...         fbWriteRegs.nQuantity     := 4;         fbWriteRegs.nMBAddr     := 16#3000;         //Tried: 16#3000, 0, 1         fbWriteRegs.cbLength     := SIZEOF(nValue);         fbWriteRegs.pSrcAddr     := ADR(nValue);         fbWriteRegs.tTimeout     := T#5S;         fbWriteRegs                (bExecute:=TRUE);     ELSE                  IF NOT fbWriteRegs.bBUSY THEN             bWriteRegs             :=FALSE;             fbWriteRegs            (bExecute:=FALSE);         END_IF                  fbWriteRegs                (bExecute:=FALSE);     END_IF  What should I change in my code in order to make this example work? Thank you in advance for any support!   Info about LabVIEW programs:  I am using the Modbus TCP Master / Slave examples  The IP address is set to localhost and the port to 502 (which should match the IP address in my Beckhoff code)  I am 100% sure it works because I have also tried connecting to this program via Python script. Picture of my LabVIEW programs: