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Jazz JZ20-J-R16 and MJ20-RS modbus Slave RS-485 problem

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I'm trying to configure Jazz JZ20-J-R16 as a SLAVE.  I've got Jazz JZ20-J-R16 (O/S Version 2.44) and Modbus module MJ20-RS.

And I'm trying to read some registers using Modbus Poll soft and ADAM-4561 converter. The Modbus Poll and ADAM works well, I can read data from another SLAVE device.

I did everything according to the manual (table from Help). The SB141 is set to 1, I can see it on the display. I am not trying to use two ports simultaneously,

only RS-485 is connected when I'm trying to read data from PLC.  When I'm trying to read data using Modbus Poll, there is "TimeOut" error.

Interestingly, when I change the connection of the communication cable (A and B), the Data Bits in PLC changes from 8 to 7, and in Modbus Poll soft is "Insufficient bytes recieved" error.


My ladder program is attached:


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