slave.
Note: This error code does not indicate the data value to write
exceed the range, but indicate the message frame is an illegal frame.
The parameter setting in parameter writing is invalid. For example,
the function input terminal cannot be set repeatedly.
In the frame message sent by the upper PC, the length of the digital
frame is incorrect or the counting of CRC check bit in RTU is different
from the lower monitor.
When the upper PC is writing or reading and the user password is set
without password unlocking, it will report that the system is locked.
The slave uses functional code fields and fault addresses to indicate it is a normal response or some
error occurs (named as objection response). For normal responses, the slave shows corresponding
function codes, digital address or sub-function codes as the response. For objection responses, the
slave returns a code which equals the normal code, but the first byte is logic 1.
For example: when the master sends a message to the slave, requiring it to read a group of address
data of the inverter function codes, there will be following function codes:
0 0 0 0 0 0 1 1 (Hex 03H)
For normal responses, the slave responds the same codes, while for objection responses, it will
return:
1 0 0 0 0 0 1 1 (Hex 83H)
Besides the function codes modification for the objection fault, the slave will respond a byte of
abnormal code which defines the error reason. When the master receives the response for the
objection, in a typical processing, it will send the message again or modify the corresponding order
To Next Page
Loading...
