Rockwell Automation 2755-G6-D Scanner with RS-232 Option - Manual (Page 53)

Serial Communication Parameters
Chapter 6
6–11
The scanner supports three levels of serial buffering:
Full Buffering, No Buffering, One Label Buffering.
Full Buffering
With Full Buffering (the default) selected, the scanner
will place all scanned labels into a 64 byte serial
transmit buffer if the host is unavailable to receive
data. This allows you to continue scanning even
though the previous label may not have been
transmitted yet. Scanning will continue normally
until the buffer is full, then scanning will stop.
Scanning will continue when enough space is
available for the current message.
Note: The buffer holds other message parameters, so
you must consider the total message length (including
label) to determine how many labels can be buffered.
See Chapter 7, Message Format Parameters.
No Buffering
When No Buffering is selected, scanning is stopped
until the current label is completely transmitted.
One Label Buffering
When One Label Buffering is selected, the scanner
will allow you to scan one more label in addition to
the label already in the transmit buffer.
NE Full Buffering *
NF No Buffering
One Label Buffering NG
Serial
Transmit Buffer