1.\" $NetBSD: joy.4,v 1.5 2004/05/11 22:42:47 wiz 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 January 7, 1996 32.Dt JOY 4 33.Os 34.Sh NAME 35.Nm joy 36.Nd game adapter driver 37.Sh SYNOPSIS 38.Cd "joy0 at isa? port 0x201" 39.Cd "joy* at isapnp?" 40.Cd "joy* at ofisa?" 41.Cd "joy* at pci?" 42.Cd "joy* at pnpbios? index ?" 43.Cd "joy* at eso?" 44.Sh DESCRIPTION 45This driver provides access to the game adapter. 46The lower bit in the 47minor device number selects the joystick: 0 is the first joystick and 481 is the second. 49.Pp 50The game control adapter allows up to two joysticks to be attached to 51the system. The adapter plus the driver convert the present resistive 52value to a relative joystick position. On receipt of an output signal, 53four timing circuits are started. By determining the time required for 54the circuit to time-out (a function of the resistance), the paddle 55position can be determined. The adapter could be used as a general 56purpose I/O card with four analog (resistive) inputs plus four digital 57input points. 58.Pp 59Applications may call 60.Xr ioctl 2 61on a game adapter driver file descriptor 62to set and get the offsets of the two potentiometers and the maximum 63time-out value for the circuit. The 64.Xr ioctl 2 65commands are listed in 66.Aq Pa machine/joystick.h 67and currently are: 68.Pp 69.Bl -tag -width JOY_GET_X_OFFSET -compact 70.It JOY_SETTIMEOUT 71Sets the maximum time-out for the adapter. 72.It JOY_GETTIMEOUT 73Returns the current maximum time-out. 74.It JOY_SET_X_OFFSET 75Sets an offset on X value. 76.It JOY_GET_X_OFFSET 77Returns the current X offset. 78.It JOY_SET_Y_OFFSET 79Sets an offset on Y value. 80.It JOY_GET_Y_OFFSET 81Returns the current Y offset. 82.El 83.Pp 84All this commands take an integer parameter. 85.Pp 86.Xr read 2 87on the file descriptor returns a 88.Fa joystick 89structure: 90.Bd -literal -offset indent 91struct joystick { 92 int x; 93 int y; 94 int b1; 95 int b2; 96}; 97.Ed 98.Pp 99The fields have the following functions: 100.Bl -tag -width xxx 101.It Fa x 102current X coordinate of the joystick (or position of paddle 1) 103.It Fa y 104current Y coordinate of the joystick (or position of paddle 2) 105.It Fa b1 106current state of button 1 107.It Fa b2 108current state of button 2 109.El 110.Pp 111The b1 and b2 fields in struct joystick are set to 1 if the 112corresponding button is down, 0 otherwise. 113.Pp 114The x and y coordinates are supposed to be between 0 and 255 for a 115good joystick and a good adapter. Unfortunately, because of the 116hardware hack that is used to measure the position (by measuring the 117time needed to discharge an RC circuit made from the joystick's 118potentiometer and a capacitor on the adapter), calibration 119is needed to determine exactly what values are returned for a specific 120joystick/adapter combination. Incorrect hardware can yield negative or 121> 255 values. 122.Pp 123A typical calibration procedure uses the values returned at lower 124left, center and upper right positions of the joystick to compute the 125relative position. 126.Pp 127This calibration is not part of the driver. 128.Sh FILES 129.Bl -tag -width Pa -compact 130.It Pa /dev/joy0 131first joystick 132.It Pa /dev/joy1 133second joystick 134.El 135.Sh SEE ALSO 136.Xr eso 4 , 137.Xr isa 4 , 138.Xr isapnp 4 , 139.Xr ofisa 4 , 140.Xr pci 4 , 141.Xr pnpbios 4 142.Sh AUTHORS 143Jean-Marc Zucconi wrote the 144.Fx 145driver. Matthieu Herrb ported it to 146.Nx 147and wrote this manual page. 148