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' This example uses the OPEN COM statement to open the COM1 port for input
' and the COM statement to enable event trapping. The ON COM statement passes
' control to a subroutine when there is activity on a terminal.
 
' Note: To run this program, you must have a terminal connected to the COM1
' port.
 
' To try this example:
' 1. Choose New Project from the File menu
' 2. Copy the code example below to the code window
' 3. Press F5 to run the example
 
 CLS                                        ' Clear the screen
                                            ' Set up error handling in
 ON ERROR GOTO ErrHandler                   ' case COM1 doesn't exist
 OPEN "COM1:9600,N,8,1,BIN" FOR INPUT AS #1 ' Open the COM port
 COM(1) ON                                  ' Turn on COM event processing
 ON COM(1) GOSUB Com1Handler                ' Set up COM event handling
 
' Wait for a COM event to occur or a key to be pressed.
 DO
 LOOP WHILE INKEY$ = ""
 COM(1) OFF                                 ' Turn off COM event handling
 CLS
 END
 
Com1Handler:
     PRINT A$; "Something was typed on the terminal attached to COM1."
     RETURN
 
ErrHandler:
     SELECT CASE ERR
          CASE 24: PRINT "COM1 is unavailable on this computer.": END
          CASE ELSE: END
     END SELECT