COMM: Modbus/RTU 32bit values

[The AList]

==> Automation List post by Eli...
To view or reply to this thread: http://www.control.com/thread/1235542857


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COMM:  Modbus/RTU 32bit values
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I am trying to read 32bit modbus registers with a Siemens S7-200 PLC and a Delta motion controller. I can do this just fine, except that I must read the 32bit register as two 16bit registers. The problem is that the two 16bit registers are read backwards. AKA if you look at the hex values...

Source:12345678
Read from Source:56781234

How do I read them in the correct order? The Siemens library only lets me read words or bits. I have thought of a couple ways to do this but I really don't want to have to write a communications buffer for every command I send and receive as there are about 15 separate 32bit values I must send and receive every cycle...
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