Communication Format
3-6
INR-244-831
3.6
Cautions for Communication
Pay attention to the following points for communication.
①
Operation after the power supply is turned on
The product cannot communicate for approx. 6 sec. after the power supply is
turned on. (No communication). Allow a time delay before starting communication
after the power supply is turned on.
②
Timing for sending and receiving
Allow a time delay for response to ensure the transition between sending from the
master and receiving when using RS-485.
③
Requesting interval
When
a “request message” is sent continuously from the master, allow an interval
of 1ms or more after receiving
the “response message” from the product.
④
Response requirements
The product will not send
a “response message” if STX and ETX (BCC) are not
included in
the “request message”. That is, if the “request message” contains an
error,
the “response message (to the error)”, including NAK and ERR, is not sent.
I
f the “response message” is not returned for a significant period after the “request
message
” is sent from the master, check the message and resend the necessary
“request message.
⑤
Address designation error
When this error occurs, the product does not respond to
a “request message”
which specifies an address other than the set one. I
f the “response message” is
not returned after a significant period, check the message and resend the
necessary
“request message”.
⑥
Number of data digits and position of decimal point
Read or written data is expressed with 5 digits, regardless of its type. Refer to
”.
⑦
Operation after
“request message to store” is received
The product begins to store data after receiving
a “request message to store”
from the master. Only the data that has a different content from the EEPROM
(data that has been changed) is stored. The time required for storage is approx. 6
sec. The product responds (sends an ACK) after the data storage is completed.
If the power supply is turned off during the storing process, the data might not be
stored. Do not turn off the power supply before the storage completion message is
received.
⑧
Storage of data other than
the “request message to store”
When a parameter is changed with a key-in operation, the product stores all
parameters into the EEPROM even if not receiving
a ”request message to store”.
