Instruction manual

5. RKC COMMUNICATION PROTOCOL
IMR01H02-E3
29
(5) NAK (Negative acknowledge)
If the controller does not receive correct data from the host computer, it sends a negative
acknowledgment NAK to the host computer. Corrections, such as re-send, must be made at the host
computer. The controller will send NAK in the following cases:
• When an error occurs on communication the line (parity, framing error, etc.)
• When a BCC check error occurs
• When the specified identifier is invalid
• When receive data exceeds the setting range
(6) No response from controller
The controller does not respond when it can not receive the selecting address, STX, ETX or BCC.
(7) EOT (Data link termination)
The host computer sends EOT when there is no more data to be sent from the host computer or there
is no response from the controller.