INST No. INE-479-P0
Software version 1.0
-19-
6.1 Time interval of data
6.2 Answer at the time of abnormality
This device answers like the following item, when there were abnormal (a faulty) in the contents
of the message from the master.
6.2.1 In case of no answer
In the following case, this device disregards the message and answers none.
(1) In case of detecting the communication error (overrun, flaming, parity, CRC, or LRC).
(2) In case that the slave address in the message is not the address of a self.
(3) In case that the data interval of the message is longer.
9600bps with the RTU mode: 10msec over 19200bps with the RTU mode: 5msec over
(Refer to [6.1 Time interval of data])
(4) In case that the communication parameter is not agreeing.
(5) In case that the received parameter is exceeding 64 bytes.
Communication speed Time interval of data
9600bps 10
m
sec
19200bps 5
m
sec
Program the time interval of the data configures 1 message within the time of the
table shown below.
In the case that the slave address is "0" at the writing function, the
implementation of the message is carried out if there is not an error in the
message.
However, it answers none.
Also, it becomes no answer even in the case that there is the above error in the
message.
Therefore, the judgment of normal/abnormality is not produced with only the
answer from this device in the case of the slave address '0'.
6. MODBUS protocol- Data interval/Answer at the time of abnormality
In the case that the time interval is longer than the above table the data is
processed as “The reception of an abnormal message'”, because the reception side
(this device) is judging as the one that the transmission from the transmission side
ended.
Caution
Reference
Reference
