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HRX-OM-S010
Chapter 5 Simple communication protocol function
5.1
Precautions for communication
HRS100/150 Series
5-2
5.1.2
Precautions for communicating
○Check the data digit number and the decimal point location when
requesting to write the set value.
○Allow a suitable interval between requests.
To send request messages in series, wait for 100msec. or longer after
receiving a response message from the product before sending the next
message.
○No response is returned for a request message of a command which is not
supported by the product.
○Retry (resend request message).
The response may not be returned due to noise. If no message is returned
after 1sec. of sending a request message, resend the request message.
○If necessary send a read request message to check if it was written
correctly.
Message to notify the completion of the process is returned when the action
for the written request message is completed.
5.1.3
Precautions after the completion of the communication
○Send the data storage request (STR) if necessary.
Data which is set by communication is stored in RAM. Set values stored in
RAM are deleted when the power supplied to the product is cut. When the
power is supplied again, operation starts with the values set before
communication (values stored in FRAM of the product).
Store the values set by communication in FRAM (rewrite FRAM) by sending
a data storage request message (STR) before cutting the power supply to
the product.
Please check how many times it is possible to write to FRAM, and avoid
unnecessary rewriting of the data during communication