Honeywell 1900GHD-2, Руководство пользователя

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• Host ACK must be set to On ( page 3-38 ).
• The host terminal software must be capable of interpreting the bar code data,
make decisions based on the data content, and send out appropriate escape
commands to the scanner.
Escape commands are addressed to the scanner via “Application Work
Groups.” Once a command is sent, all scanners in a group respond to that com-
mand. Because of this,
it is recommended that each scanner is assigned to
its own group in Host ACK mode .
The commands to which the scanner responds are listed on page 3-38 . The
<ESC> is a 1B in hex. A typical command string is y <ESC> x, where “y” is the
application work group number, “<ESC> x” is the escape command, and the
comma is the terminator, which is required.
Commands may be strung together to create custom response sequences. An
example of a command string is listed below.
0<ESC>4<ESC>5<ESC>6,
The above example will make a scanner in application work group zero beep
low, then medium, then high.
Once Host ACK is enabled, the system works as follows:
• The scanner reads a code and sends data to the base or Access Point to
transmit to the host system. No audible or visual indication is emitted until the
scanner receives an escape command. The scanner read illumination goes
out when there’s a successful read.
• Scanner operation is suspended until 1) a valid escape string is received from
the host system (via the base or Access Point) or 2) the scanner times out.
• Once condition 1 or 2 above has been met, the scanner is ready to scan
again, and the process repeats.
A time-out occurs if the scanner does not receive a valid escape command
within 10 seconds. A time-out is indicated by an error tone. If a time-out occurs,
the operator should check the host system to understand why a response to the
scanner was not received.