QBasic 1.1: ON PEN Statement

Explanation

PEN, ON PEN Statements

PEN enables, disables, or suspends light-pen event trapping. If event trapping is enabled, ON PEN branches to a subroutine whenever the light pen is activated.

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You are here: References Overview > QBasic 1.1 Commands List > ON PEN Statement

Syntax

PEN ON

PEN OFF

PEN STOP

ON PEN GOSUB line

Description / Parameter(s)

PEN ON	Enables light-pen event trapping.
PEN OFF	Disables light-pen event trapping.
PEN STOP	Suspends light-pen event trapping. Events are processed once event trapping is enabled by PEN ON.
line	The label or number of the first line of the event-trapping subroutine.

Example


    'This example requires a light pen.
    ON PEN GOSUB Handler
    PEN ON
    PRINT "Press Esc to exit."
    DO UNTIL INKEY$ = CHR$(27): LOOP
    END
 
Handler:
    PRINT "Pen is at row"; PEN(6); ", column"; PEN(7)
    RETURN