6. RKC COMMUNICATION
IMS01J02-E4
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(4) EOT send (Ending data transmission from the SR Mini HG SYSTEM)
In the following cases, the SR Mini HG SYSTEM sends EOT to terminate the data link:
When the specified identifier is invalid
When there is an error in the data format
When all the data has been sent
(5) No response from the SR Mini HG SYSTEM
The SR Mini HG SYSTEM will not respond if the polling address is not received correctly. It may be
necessary for the host computer to take corrective action such as a time-out.
(6)
ACK (Acknowledgment)
An acknowledgment ACK is sent by the host computer when data received is correct. When the SR
Mini HG SYSTEM receives ACK from the host computer, the SR Mini HG SYSTEM will send any
remaining data of the next identifier without additional action from the host computer.
For the identifier, see
6.2 Communication Identifier List (P. 65)
.
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 SR Mini HG SYSTEM, it sends a negative
acknowledgment NAK to the SR Mini HG SYSTEM. The SR Mini HG SYSTEM 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 SR Mini HG
SYSTEM sends data, the SR Mini HG SYSTEM sends EOT to terminate the data link (time-out time:
about 3 seconds).
(9) Indefinite response from host computer
The SR Mini HG SYSTEM 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
SR Mini HG SYSTEM or to terminate the data link due lack of response from the SR Mini HG
SYSTEM.