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3.6 Things to Be Noted during the Communication
3.6.1 Timing of Transmission
Upon using RS-485, set enough response delay time to ensure the communication (sending/receiving)
with the host computer.
See Figure of "3.1 Communication Procedures" and "2.8 Setting of Response Delay Time."
3.6.2 Request Interval
If the "request message" is to be sent continuously by the upper computer, wait for at least
2msecs. from the arrival of the "response message" from this product before sending the next
request message.
3.6.3 Conditions for Response
This product will not return the "response message" if STX and ETX (BCC) are not included in
the "request message."
Therefore, although there is an error in the "request message," the "response message" with NAK
And ERR will not be returned unless the above condition is met.
Therefore, the upper computer should resend the necessary "request message" if the "response
message" is not returned within the reasonable time.
Once STX is received, this product clears all codes that were received prior to the said STX.
3.6.4 Address Specification Error
This product will not respond to any "request message" that specifies the address that is other
than the one that has been set to itself.
Therefore, if there is an error in the address section of the "request message," none of the slave
stations will return the "response message."
Therefore, the upper computer should resend the necessary "request message" if the "response
message" is not returned within the reasonable time.
Once STX is received, this product clears all codes that were received prior to the said STX.
3.6.5 Number of Digits of Data and Position of Decimal Point
See "3.5 Explanation a
bout Codes ⑤ Numerical Data
."
3.6.6 Operation After the Receiving of Save Request Message
This product starts the saving of data once it receives the save request message correctly from
the upper computer.
Only the data that is different from the one stored in the EEPROM (changed data) shall be saved.
Time that is required to save the data (TW) is within 6 seconds.
The product sends a response (ACK) when the saving of data is completed.
Some data may be lost if the product is turned OFF while the saving process is in progress. Do not
turn the power of this product OFF for at least 6 seconds after the sending of the save request message.
3.6.7 Upon Turning the Power ON
This product will not perform any communication for approximately 4 seconds after turning its power
ON (no response). Set the delay from power ON to start communication.
3.6.8 Saving the Data Other than Save Request Message
This product saves the parameter into the EEPROM even without receiving the save request message
In case of the following:
1) If the parameter is changed through key operation, it writes only changed parameters and
other related parameters.
2) If the auto tuning is activated and ended normally, only the PID constant will be written.
3.6.9 Change of Setting Value (SV or SV2) by the Communication during Auto Tuning
If the value for control (SV or SV2) is changed via communication while the auto tuning is performed,
the said value (SV or SV2) will not be changed until auto tuning ends.
