4. COMMUNICATION PROTOCOL
IMCB03-E3
26
(5) Negative acknowledge [NAK]
The controller sends [NAK] in the following cases. Then the appropriate recovery processing steps,
such as data resend on the host computer side should be taken.
!
When an error occurs on the line (parity, framing error, etc.).
!
When a BCC check error occurs.
!
When there is no identifier.
!
When receive data is not in the specified configuration
(Text is not in the "Identifier + data construction.")
!
When the number of receive data digits exceeds 6.
!
When normally receive data exceeds the setting range.
!
When the identifier not added to the controller is specified.
(6) No response
If the selecting address is not received correctly, the controller is set to no response, if [STX], [ETX]
and [BCC] is not received correctly, the controller is also set to no response.
(7) Data link termination [EOT]
When terminating the data link because there was no more to be sent on the host computer side or the
controller was set to no response, send [EOT] from the host computer.