APPENDIX. HOST COMMUNICATION PROTOCOL
IMR02E20-E1
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(5) NAK (Negative acknowledge)
If the SRZ unit 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 send conditions of NAK (after reception of ETX or BCC)
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
When receive data is the identifier of RO (read only)
When the module related to the identifier received by the SRZ is not connected
The send conditions of NAK (after reception of ETB or BCC)
When a BCC check error occurs
(6) No response from SRZ unit
The SRZ unit does not respond when it cannot receive the selecting address, STX, ETB, 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 SRZ unit.
