Roman,
without digging into MODBUS protocol and exactly checking every byte of the
sequence you have shown here: the missing bytes are the data bytes, means they
are influenced by the data you set at the input of the MODBUS-plug-in. In other
direction - when you receive some data - these bytes are changed from your
device, there they contain the data you read from it.
--
Kind regards
Jim Hart
http://www.lasermarkingsoftware.com
http://www.openapc.com
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