3. RKC COMMUNICATION PROTOCOL
IMR02F04-E1
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(4) ACK (Acknowledgment)
An acknowledgment ACK is sent by the PG500 when data received is correct. When the host computer
receives ACK from the PG500, the host computer will send any remaining data. If there is no more data to
be sent to the PG500, the host computer sends EOT to terminate the data link.
(5) NAK (Negative acknowledge)
If the PG500 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 PG500
will send NAK in the following cases:
When an error occurs on communication the line (parity, framing error, etc.)
When a BCC check error occurs
When there is an error in the data.
When receive data exceeds the setting range
When the specified identifier is invalid
When receive data is the identifier of RO (read only)
(6) No response from PG500
The PG500 does not respond when it cannot receive the selecting address, STX, 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 PG500.
