Yamato DKG610 Instruction Manual page 48

⑦ BCC
This is a check code for error detection and is an exclusive OR（EX-OR） of all characters
from STX to ETX. This code (BCC) will not be embedded in a reply message when the item
BCC check for communication setting is set to "None".
⑧ ACK
This is an acknowledgement code and is returned embedded in a "reply message" from the
Unit when the message received with the Unit contains no error.
⑨ NAK
This is a negative acknowledgement code and is returned embedded in a "reply message"
from the Unit when the "request message" received with the Unit contains an error.
⑩ ERR type
When a "request message" received with the Unit contains an error, its description is
embedded after "⑨NAK" in the "reply message" from the Unit.
This is a communication error and its detailed expression is omitted here.
Reception timeout means a case STX is not sent from the Unit after some response wait time
after a host PC has sent BCC.
4. Operating procedures
Option (RS485 communication function)
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