3. RKC COMMUNICATION PROTOCOL
IMR02F04-E1
21
(6) ACK (Acknowledgment)
An acknowledgment ACK is sent by the host computer when data received is correct.
When the PG500 receives ACK from the host computer, the PG500 will send any remaining data of
the next identifier without additional action from the host computer.
For the identifier, refer to
5. COMMUNICATION DATA LIST (P. 42)
.
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 PG500, it sends a negative
acknowledgment NAK to the PG500. The PG500 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 PG500 sends
data, the PG500 sends EOT to terminate the data link. (Time out: 3 seconds)
(9) Indefinite response from host computer
The PG500 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
PG500 or to terminate the data link due lack of response from the PG500.
