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The _DEVICEINPUT function returns the device number when a controller device button, wheel or axis event occurs.


device% = _DEVICEINPUT
device_active% = _DEVICEINPUT(device_number%)


  • Use the _DEVICEINPUT device% INTEGER returned to find the number of the controller device being used.
  • A literal specific device_number% parameter can be used to return -1 if active or 0 if inactive. EX: WHILE _DEVICEINPUT(2)


  • Use _DEVICES to find the number of controller devices available BEFORE using this function.
  • _DEVICE$ can be used to list the device names and control types using valid _DEVICES numbers.
  • When a device button is pressed or a scroll wheel or axis is moved, the device number will be returned.
  • Devices are numbered as 1 for keyboard and 2 for mouse. Other controller devices will be numbered 3 or higher if installed.
  • _LASTBUTTON, _LASTAXIS, or _LASTWHEEL will indicate the number of functions available with the specified device number.
  • User input events can be monitored reading valid numbered _AXIS, _BUTTON, _BUTTONCHANGE or _WHEEL functions.
  • Note: ON _DEVICEINPUT GOSUB keyboard, mouse, gamecontrol can be used to control the devices 1,2 and 3, etc.


Example 1: Checking device controller interfaces and finding out what devices are being used.

FOR i = 1 TO _DEVICES PRINT STR$(i) + ") " + _DEVICE$(i) PRINT "Button:"; _LASTBUTTON(i); ",Axis:"; _LASTAXIS(i); ",Wheel:"; _LASTWHEEL(i) NEXT PRINT DO x = _DEVICEINPUT IF x THEN PRINT "Device ="; x; LOOP UNTIL INKEY$ = CHR$(27) 'escape key exit END

[KEYBOARD][BUTTON] Buttons: 512 Axis: 0 Wheels: 0 [MOUSE][BUTTON][AXIS][WHEEL] Buttons: 3 Axis: 2 Wheels: 3 [CONTROLLER][[NAME][Microsoft Sidewinder Precision Pro (USB)]][BUTTON][AXIS] Buttons: 9 Axis: 6 Wheels: 0 Device = 2 Device = 2

Note: Mouse events must be within the program screen area. Keyboard presses are registered only when program is in focus.

Example 2: Why does a mouse have 3 wheels? Relative x and y movements can be read using the first 2 _WHEEL reads.

ignore = _MOUSEMOVEMENTX 'dummy call to put mouse into relative movement mode PRINT "Move your mouse and/or your mouse wheel (ESC to exit)" d = _DEVICES ' always read number of devices to enable device input DO: _LIMIT 30 'main loop DO WHILE _DEVICEINPUT(2) 'loop only runs during a device 2 mouse event PRINT _WHEEL(1), _WHEEL(2), _WHEEL(3) LOOP LOOP UNTIL INKEY$ = CHR$(27)

Explanation: Referencing the _MOUSEMOVEMENTX function hides the mouse and sets the mouse to a relative movement mode which can be read by _WHEEL. _DEVICEINPUT(2) returns -1 (true) only when the mouse is moved, scrolled or clicked.

Example 3: Using ON...GOSUB with the _DEVICEINPUT number to add keyboard, mouse and game controller event procedures.

n = _DEVICES 'required when reading devices PRINT "Number of devices found ="; n FOR i = 1 TO n PRINT i; _DEVICE$(i) ' 1 = keyboard, 2 = mouse, 3 = other controller, etc. NEXT PRINT DO: device = _DEVICEINPUT ON device GOSUB keyboard, mouse, controller 'must be inside program loop LOOP UNTIL INKEY$ = CHR$(27) END keyboard: PRINT device; "Keyboard"; RETURN mouse: PRINT device; "Mouse "; RETURN controller: PRINT device; "Game control "; RETURN

Code by Ted Weissgerber
Note: ON...GOSUB and ON...GOTO events require numerical values to match the order of line labels listed in the event used inside loops.

See also

Keyword Reference - Alphabetical
Keyword Reference - By Usage
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