QBasic 1.1: COM Statement

Explanation

COM, ON COM Statements

COM enables, disables, or suspends event trapping on a communications port. If event trapping is enabled, ON COM branches to a subroutine whenever characters are received at the port.

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Syntax

COM(n%) ON

COM(n%) OFF

COM(n%) STOP

ON COM(n%) GOSUB line

Description / Parameter(s)

n%	The number of a COM (serial) port (1 or 2).
COM(n%) ON	Enables trapping of a communications event.
COM(n%) OFF	Disables communications event trapping.
COM(n%) STOP	Suspends communications event trapping. Events are processed once event trapping is enabled by COM ON.
line	The label or number of the first line of the event-trapping subroutine.

Example


COM(1) ON       'Enable event trapping on port 1.
ON COM(1) GOSUB ComHandler
DO : LOOP WHILE INKEY$ = ""
COM(1) OFF
END

ComHandler:
  PRINT "Something was typed at the terminal attached to COM1."
  RETURN