Paxar Gold 6037EX, Руководство программиста

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Programming Techniques 6-5
B u i l d i n g P a c k e t s D y n a m i c a l l y
An application can use fixed packets or packets that change
every time they are used, such as in an application where the
operator enters the quantity for the batch. When packets
change every time they are used, the application must build the
packet dynamically.
SAMPLE3.C in the Samples sub-directory illustrates building
packets dynamically.
U s i n g t h e S c a n n e r
An application uses the printer’s scanner to read bar codes as
follows:
1. Enable the scanner with scnScannerOpen or
scnOpenScannerShared.
2. If necessary, configure the scanner using the scnGet
xxx
and scnSet
xxx
functions.
3. Use any scanner function to operate the scanner. These
functions are described in Chapter 4 and all begin with an
scn
prefix.
4. Disable the scanner with scnCloseScanner.
SAMPLE5.C in the Samples sub-directory illustrates how to use
the scanner.
R e a d i n g T r i g g e r P u l l s
Pressing any key (including pulling the trigger) sends a code to
the application for it to read. The trigger emulates an F11 as an
extended character code. To read a trigger pull, the application
reads two characters. If the first character is a zero and the
second is 0x85, the operator pulled the trigger.
SAMPLE1.C in the Samples sub-directory illustrates reading
trigger pulls.