Rockwell Automation 2755 AtomScan Bar Code Reader - Manual (Page 98)

6–13 Hardware Operation
Publication 2755-6.9
Full-duplex allows the auxiliary monitor data and bar code data to be
sent directly to the host. The bar code data is not displayed on the
auxiliary monitor screen.
When Then
Data is initiated from the monitor
•
monitor data is passed directly through the host
whenever it is received by the reader, unless the
reader is in a polled mode, in which case the data
will be ignored.
•
monitor data is not echoed.
•
monitor data to the host will not have a preamble
or a postamble.
•
a <D> command is the only command accepted
by the decoder from the monitor. All other
commands will pass through to the host.
Data is initiated from the reader
•
scan data is not sent to the monitor.
Data is initiated from the host
•
in a polled mode, data echoed from the host to
the monitor must be in the format <B_>.
•
in unpolled mode, all host data is echoed to the
monitor.
Half-duplex operates exactly like Full-duplex except that the bar
code data is displayed on the auxiliary monitor screen at the same
time the data is sent to the host.
When Then
Data is initiated from the monitor
•
monitor data to the host is ignored if the reader is
in a polled mode.
•
monitor data or scanned data is sent to the host
whenever it is received.
•
monitor data is not echoed.
•
monitor data to the host will not have a preamble
or a postamble.
•
a <D> command is the only command accepted
by the decoder from the monitor. All other
commands will pass through to the host.
Data is initiated from the reader
•
scan data is transmitted to the monitor at the
same time it is transmitted to the host.
•
transmission to the host conforms to all the
parameters specified in the configuration menu.
Data is initiated from the host
•
in a polled mode, data echoed from the host to
the monitor must be in the format <B_>.
•
in unpolled mode, all host data is echoed to the
monitor.