Cino FA470 - Manual (Page 13)

Command Overview
1-6
Parameter Format
Generally, there are two different parameter formats, “Command with Simple Parameter(s)”
and “Command with Compound Parameters”.
Commands with simple parameters
The Action, Acknowledgement, Data and Image commands belong to this group.
1) Action
The parameter filed of Action commands can be “Null” or several option bytes. The
following table shows the structure of Parameter(s) field:
Parameter(s)
First byte of the parameter …… Last byte of the parameter
Options …… Options
If the device successfully received the action command issued by the host, a “Device
ACK” will be sent to the host right after the device performed the action. Otherwise, a
“Device NAK” will be sent to host to issue a command error
If the host can’t receive any reaction within the user preset time-out duration, this can be
considered as a transmission failure. In this case, you are recommended to check the
cable connection, power supply, setting of communication profile, and so on.
2) Acknowledgement command
There are four Acknowledge commands including “Device ACK”, “Device NAK”, “Host
ACK” and “Host NAK”. All Acknowledgement commands have no parameters, it means
the parameter field of those commands has to be set to “null”.
3) Data
The Decode Data is a special command, and it has to be considered as an unconditional
event. If the “Data Transmission Packet” parameter is set to “Enable”, the scanner will
send a
Packed Decode Data Message rather than a Raw Data message to the host after
a successful decode. The actual decoded data will be put into the Parameter(s) field of
Decode Data message string. Differently, the Transmit Record command is used to
retrieve records from the scanner. Scanner send back the stored records as reply.
4) Image
Image commands is used to capture image, which is available for A series scanner. Enter/
Exit Capture Image Mode formatted like Action command, scanner replies ACK/NAK.
Capture Image Ready Notify is similar to Decode Data which is sent from the scanner to
the host. And the format of Get Capture Image Data is like Transmit Record command,
which is used to retrieve data from the scanner.