27
RS-232 DEMONSTRATION PROGRAM
If an RS-232 scanner is not communicating with your IBM compatible PC, key
in the following BASIC program to test that the communication port and
scanner are working. This program is for demonstration purposes only. It is
only intended to prove that cabling is correct, the com port is working, and the
scanner is working. If the bar code data displays on the screen while using
this program, it only demonstrates that the hardware interface and scanner
are working. At this point, investigate whether the application software and
the scanner configuration match. If the application does not support RS-232
scanners, a software wedge program that will take RS-232 data and place it
into a keyboard buffer may be needed. This program tells the PC to ignore
RTS-CTS, Data Set Ready (DSR) and Data Carrier Detect (DCD) signals. If
the demonstration program works and yours still does not, jumper RTS to
CTS and Data Terminal Reading (DTR) to DCD and DSR on the back of your
PC.
10 CLS
20 ON ERROR GOTO 100
30 OPEN “COM1:9600,S,7,1,CS0,DS0,CD0,LF” AS #1
35 PRINT “SCAN A FEW BAR CODES”
40 LINE INPUT #1, BARCODE$
50 PRINT BARCODE$
60 K$ = INKEY$: IF K$ = CHR$(27) THEN GOTO 32766
70 GOTO 40
100 PRINT “ERROR NO.”; ERR; “ PRESS ANY KEY TO TERMINATE.”
110 K$ = INKEY$: IF K$ = “” THEN GOTO 110
32766 CLOSE: SYSTEM
32767 END