5. RKC COMMUNICATION PROTOCOL
IMR01J08-E1
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(6) ACK (Acknowledgment)
An acknowledgment ACK is sent by the host computer when data received is correct. When the
controller receives ACK from the host computer, the controller will send any remaining data of the
next identifier without additional action from the host computer.
For the identifier, see
5.3 Communication Identifier List (P. 22)
.
When host computer determines to terminate the data link, EOT is sent from the host computer.
(7) NAK (Negative acknowledge)
If the host computer does not receive correct data from the controller, it sends a negative
acknowledgment NAK to the controller. The controller will re-send the same data when NAK is
received. This cycle will go on continuously until either recovery is achieved or the data link is
corrected at the host computer.
(8) No response from host computer
When the host computer does not respond within approximately three seconds after the controller
sends data, the controller sends EOT to terminate the data link.
(9) Indefinite response from host computer
The controller sends EOT to terminate the data link when the host computer response is indefinite.
(10) EOT (Data link termination)
The host computer sends EOT message when it is necessary to suspend communication with the
controller or to terminate the data link due lack of response from the controller.
