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\n";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>