9 .Nd joystick device driver
11 To compile this driver into the kernel,
12 place the following lines in your
13 kernel configuration file:
14 .Bd -ragged -offset indent
18 Alternatively, to load the driver as a
19 module at boot time, place the following line in
21 .Bd -literal -offset indent
26 .Pa /boot/device.hints :
27 .Cd hint.joy.0.at="isa"
28 .Cd hint.joy.0.port="0x201"
29 .Cd hint.joy.1.at="isa"
30 .Cd hint.joy.1.port="0x201"
34 The joystick device driver allows applications to read the status of
37 This device may be opened by only one process at a time.
39 The joystick status is read from a structure via a read()
41 The structure is defined in the header file as follows:
43 .Bd -literal -offset indent
45 int x; /* x position */
46 int y; /* y position */
47 int b1; /* button 1 status */
48 int b2; /* button 2 status */
52 Positions are typically in the range 0-2000.
53 .Ss One line perl example:
55 perl -e 'open(JOY,"/dev/joy0")||die;while(1)
56 {sysread(JOY,$x,16);@j=unpack("iiii",$x);print "@j\\n";sleep(1);}'
59 Several ioctl() calls are also available.
60 They take an argument of
62 .Bl -tag -width JOY_SET_X_OFFSET
63 .It Dv JOY_SETTIMEOUT Fa int *limit
64 Set the time limit (in microseconds) for reading the joystick
67 too small may prevent to get correct values for the positions (which
68 are then set to -2147483648), however this can be useful if one is
69 only interested by the buttons status.
70 .It Dv JOY_GETTIMEOUT Fa int *limit
71 Get the time limit (in microseconds) used for reading the joystick
73 .It Dv JOY_SET_X_OFFSET Fa int *offset
74 Set the value to be added to the X position when reading the joystick
76 .It Dv JOY_SET_Y_OFFSET Fa int *offset
77 Set the value to be added to the Y position when reading the joystick
79 .It Dv JOY_GET_X_OFFSET Fa int *offset
80 Get the value which is added to the X position when reading the joystick
82 .It Dv JOY_GET_Y_OFFSET Fa int *offset
83 Get the value which is added to the Y position when reading the joystick
86 .Sh TECHNICAL SPECIFICATIONS
87 The pinout of the DB-15 connector is as follow:
91 3 X1 (potentiometer #1)
94 6 Y1 (potentiometer #2)
99 11 X2 (potentiometer #3)
101 13 Y2 (potentiometer #4)
106 Pots are normally 0-150k variable resistors (0-100k sometimes), and
107 according to the IBM technical reference, the time is given by
108 Time = 24.2e-6s + 0.011e-6s * R/Ohms
110 .Bl -tag -width /dev/joy?
112 joystick device files
120 .An Jean-Marc Zucconi Aq jmz@cabri.obs-besancon.fr