1.\" $NetBSD: joy.4,v 1.9 2010/03/22 18:58:31 joerg Exp $ 2.\" 3.\" Copyright (c) 1996 Matthieu Herrb 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 3. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by Christopher G. Demetriou. 17.\" 4. The name of the author may not be used to endorse or promote products 18.\" derived from this software without specific prior written permission 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23.\" IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30.\" 31.Dd July 22, 2006 32.Dt JOY 4 33.Os 34.Sh NAME 35.Nm joy 36.Nd game adapter driver 37.Sh SYNOPSIS 38.Cd "joy* at acpi?" 39.Cd "joy* at eap?" 40.Cd "joy* at eso?" 41.Cd "joy0 at isa? port 0x201" 42.Cd "joy* at isapnp?" 43.Cd "joy* at ofisa?" 44.Cd "joy* at pci?" 45.Cd "joy* at pnpbios? index ?" 46.Sh DESCRIPTION 47This driver provides access to the game adapter. 48The lower bit in the minor device number selects the joystick: 0 49is the first joystick and 1 is the second. 50.Pp 51The game control adapter allows up to two joysticks to be attached to 52the system. 53The adapter plus the driver convert the present resistive value to 54a relative joystick position. 55On receipt of an output signal, four timing circuits are started. 56By determining the time required for the circuit to time-out (a 57function of the resistance), the paddle position can be determined. 58The adapter could be used as a general purpose I/O card with four 59analog (resistive) inputs plus four digital input points. 60.Pp 61Applications may call 62.Xr ioctl 2 63on a game adapter driver file descriptor 64to set and get the offsets of the two potentiometers and the maximum 65time-out value for the circuit. 66The 67.Xr ioctl 2 68commands are listed in 69.In machine/joystick.h 70and currently are: 71.Pp 72.Bl -tag -width JOY_GET_X_OFFSET -compact 73.It Dv JOY_SETTIMEOUT 74Sets the maximum time-out for the adapter. 75.It Dv JOY_GETTIMEOUT 76Returns the current maximum time-out. 77.It Dv JOY_SET_X_OFFSET 78Sets an offset on X value. 79.It Dv JOY_GET_X_OFFSET 80Returns the current X offset. 81.It Dv JOY_SET_Y_OFFSET 82Sets an offset on Y value. 83.It Dv JOY_GET_Y_OFFSET 84Returns the current Y offset. 85.El 86.Pp 87All these commands take an integer parameter. 88.Pp 89.Xr read 2 90on the file descriptor returns a 91.Fa joystick 92structure: 93.Bd -literal -offset indent 94struct joystick { 95 int x; 96 int y; 97 int b1; 98 int b2; 99}; 100.Ed 101.Pp 102The fields have the following functions: 103.Bl -tag -width xxx 104.It Fa x 105current X coordinate of the joystick (or position of paddle 1) 106.It Fa y 107current Y coordinate of the joystick (or position of paddle 2) 108.It Fa b1 109current state of button 1 110.It Fa b2 111current state of button 2 112.El 113.Pp 114The b1 and b2 fields in struct joystick are set to 1 if the 115corresponding button is down, 0 otherwise. 116.Pp 117The x and y coordinates are supposed to be between 0 and 255 for a 118good joystick and a good adapter. 119Unfortunately, because of the 120hardware hack that is used to measure the position (by measuring the 121time needed to discharge an RC circuit made from the joystick's 122potentiometer and a capacitor on the adapter), calibration 123is needed to determine exactly what values are returned for a specific 124joystick/adapter combination. 125Incorrect hardware can yield negative or values greater than 255. 126.Pp 127A typical calibration procedure uses the values returned at lower 128left, center and upper right positions of the joystick to compute the 129relative position. 130.Pp 131This calibration is not part of the driver. 132.Sh FILES 133.Bl -tag -width Pa -compact 134.It Pa /dev/joy0 135first joystick 136.It Pa /dev/joy1 137second joystick 138.El 139.Sh SEE ALSO 140.Xr acpi 4 , 141.Xr eap 4 , 142.Xr eso 4 , 143.Xr isa 4 , 144.Xr isapnp 4 , 145.Xr ofisa 4 , 146.Xr pci 4 , 147.Xr pnpbios 4 148.Sh AUTHORS 149Jean-Marc Zucconi wrote the 150.Fx 151driver. 152Matthieu Herrb ported it to 153.Nx 154and wrote this manual page. 155