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MODBUS TCP Error 56

Hello,

 

I am having trouble with MODBUS TCP communication.  I am trying to read the input registers on a master.vi after a slave.vi has written to it.  Attached you will find my slave and master vi's.  I have made sure I had the correct IP address, same starting address for master and slave, and also the same port number.  The input register is array size 4 and I've also wired that in on the master for the quantity to read.  Could someone please give me some pointers?

 

Greatly appreciated!

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I found my problem.  I was missing the TCP communication in the slave.vi.

Thanks

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