I am getting problem when AB Micrologix Modbus communication with Conzerv EM643.

I have converted EM6400 RS485 port to RS232 and configured all setting as per documents. my MSG instruction showing error "Modbus exception code 02 returned: Illegal data address"

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Either you are asking for a register which doesn't exist, or you are trying to read mis-aligned 32-bit data.

For example, a meter might have a 32-bit float in say 4x10001 and 4x10002. Many device won't allow you to start reading at 4x10002... you'd need to start at 4x10001 or 4x10003.

Life is worse since some hosts would expect 4x10001 to be entered as 10000 (off-by-one).

 

Yes Thank you, as you suggested I started address as per document. Now I am getting another error "Bad parameters in reply data packets, could not be process by local processor"