JOY(4)							   BSD Kernel Interfaces Manual 						    JOY(4)

NAME

     joy -- joystick device driver

SYNOPSIS

     To compile this driver into the kernel, place the following lines in your kernel configuration file:

	   device joy

     Alternatively, to load the driver as a module at boot time, place the following line in loader.conf(5):

	   joy_load="YES"

     In /boot/device.hints:
     hint.joy.0.at="isa"
     hint.joy.0.port="0x201"
     hint.joy.1.at="isa"
     hint.joy.1.port="0x201"

     #include <sys/joystick.h>

DESCRIPTION

     The joystick device driver allows applications to read the status of the PC joystick.

     This device may be opened by only one process at a time.

     The joystick status is read from a structure via a read() call.  The structure is defined in the header file as follows:

		   struct joystick {
			   int x;	  /* x position */
			   int y;	  /* y position */
			   int b1;	  /* button 1 status */
			   int b2;	  /* button 2 status */
		   };

     Positions are typically in the range 0-2000.

   One line perl example:
     perl -e 'open(JOY,"/dev/joy0")||die;while(1)
     {sysread(JOY,$x,16);@j=unpack("iiii",$x);print "@j
";sleep(1);}'

   ioctl calls
     Several ioctl() calls are also available.	They take an argument of type int *

     JOY_SETTIMEOUT int *limit
		       Set the time limit (in microseconds) for reading the joystick status.  Setting a value too small may prevent to get correct
		       values for the positions (which are then set to -2147483648), however this can be useful if one is only interested by the
		       buttons status.

     JOY_GETTIMEOUT int *limit
		       Get the time limit (in microseconds) used for reading the joystick status.

     JOY_SET_X_OFFSET int *offset
		       Set the value to be added to the X position when reading the joystick status.

     JOY_SET_Y_OFFSET int *offset
		       Set the value to be added to the Y position when reading the joystick status.

     JOY_GET_X_OFFSET int *offset
		       Get the value which is added to the X position when reading the joystick status.

     JOY_GET_Y_OFFSET int *offset
		       Get the value which is added to the Y position when reading the joystick status.

TECHNICAL SPECIFICATIONS

     The pinout of the DB-15 connector is as follow:

       1  XY1 (+5v)
       2  Switch 1
       3  X1 (potentiometer #1)
       4  Switch 1 (GND)
       5  Switch 2 (GND)
       6  Y1 (potentiometer #2)
       7  Switch 2
       8  N.C.
       9  XY2 (+5v)
      10  Switch 4
      11  X2 (potentiometer #3)
      12  Switch 3&4 (GND)
      13  Y2 (potentiometer #4)
      14  Switch 3
      15  N.C.

     Pots are normally 0-150k variable resistors (0-100k sometimes), and according to the IBM technical reference, the time is given by Time =
     24.2e-6s + 0.011e-6s * R/Ohms

FILES

     /dev/joy?	joystick device files

HISTORY

     The joy driver appeared in FreeBSD 2.0.5.

AUTHORS

     Jean-Marc Zucconi <jmz@cabri.obs-besancon.fr>

BSD
								 January 23, 1995							       BSD