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HRX-OM-S010
Chapter 4 MODBUS communication function
HRS100/150 Series
4.4
Communication sequence
4-7
4.4 Communication sequence
Starts with a request message from the
customer’s system (host), and
finishes with a response message from the product (slave). This product
operates as a slave. It does not send any requests.
●Positive response
Based on the request message, reads
register/writes register and returns a positive
response.
●Negative response
Returns a negative message when the received
request message is not normal. Refer to ‘’4.9
’’.
●No response
No response is returned when there is an error in
“slave address specification” or ”LRC”.
Customer's system
(host)
This product
(slave)
Request message
Positive res
ponse
Request message
Negative re
sponse
Request message
No response
10
~
200ms
(
Response me
ssage
)
(
Response me
ssage
)