27
RS232 DEMONSTRATION PROGRAM
If an RS232 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