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diff --git a/share/man/man4/led.4 b/share/man/man4/led.4 new file mode 100644 index 0000000..b31a083 --- /dev/null +++ b/share/man/man4/led.4 @@ -0,0 +1,193 @@ +.\" Copyright (c) 2003 Sergey A. Osokin <osa@FreeBSD.org> +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd April 24, 2007 +.Dt LED 4 +.Os +.Sh NAME +.Nm led +.Nd API for manipulating LED's, lamps and other annunciators +.Sh SYNOPSIS +.In dev/led/led.h +.Pp +.Fd "typedef void led_t(void *priv, int onoff);" +.Ft struct cdev * +.Fn led_create_state "led_t *func" "void *priv" "char const *name" "int state" +.Ft struct cdev * +.Fn led_create "led_t *func" "void *priv" "char const *name" +.Ft void +.Fn led_destroy "struct cdev *" +.Sh DESCRIPTION +The +.Nm +driver provides generic support for handling LEDs, lamps and other +annunciators. +.Pp +The hardware driver must supply a function to turn the annunciator on and off +and the device +.Fa name +of the annunciator relative to +.Pa /dev/led/ . +The +.Fa priv +argument is passed back to this on/off function and can be used however +the hardware driver sees fit. +.Pp +The lamp can be controlled by opening and writing +.Tn ASCII +strings to the +.Pa /dev/led/bla +device. +.Pp +In the following, we will use this special notation to indicate the resulting +output of the annunciator: +.Pp +.Bl -tag -width indent -offset indent -compact +.It Ic * +The annunciator is on for 1/10th second. +.It Ic _ +The annunciator is off for 1/10th second. +.El +.Pp +State can be set directly, and since the change happens immediately, +it is possible to flash the annunciator with very short periods and +synchronize it with program events. +It should be noted that there is a non-trivial overhead, so this may +not be usable for benchmarking or measuring short intervals. +.Pp +.Bl -tag -width indent -offset indent -compact +.It Ic 0 +Turn the annunciator off immediately. +.It Ic 1 +Turn the annunciator on immediately. +.El +.Pp +Flashing can be set with a given period. +The pattern continues endlessly. +.Pp +.Bl -tag -width indent -offset indent -compact +.It Ic f +_* +.It Ic f1 +_* +.It Ic f2 +__** +.It Ic f3 +___*** +.It ... +.It Ic f9 +_________********* +.El +.Pp +Three high-level commands are available: +.Bl -tag -width indent -offset indent +.It Ic d%d +Numbers. +Each digit is blinked out at 1/10th second, zero as ten pulses. +Between digits a one second pause and after the last +digit a two second pause after which the sequence is repeated. +.It Ic s%s +String. +This gives full control over the annunciator. +Letters +.Ql A +.No ... +.Ql J +turn the annunciator on for from 1/10th to one full +second. +Letters +.Ql a +.No ... +.Ql j +turn the annunciator off for 1/10th +to one full second. +Letters +.Ql u +and +.Ql U +turn the annunciator off and on respectively when the next +UTC second starts. +Unless terminated with a +.Ql \&. , +the sequence is immediately repeated. +.It Ic m%s +Morse. +.Pp +.Bl -tag -width indent -offset indent -compact +.It Ql \&. +becomes +.Ql _* +.It Ql - +becomes +.Sq Li _*** +.It Ql "\ " +becomes +.Sq Li __ +.It Ql \en +becomes +.Sq Li ____ +.El +.El +.Pp +The sequence is repeated after a one second pause. +.Sh FILES +.Bl -tag -width ".Pa /dev/led/*" +.It Pa /dev/led/* +.El +.Sh EXAMPLES +A +.Sq Li d12 +flashes the lamp +.Pp +.Dl *__________*_*______________________________ +.Pp +A +.Sq Li sAaAbBa +flashes +.Pp +.Dl *_*__**_ +.Bd -literal +/usr/games/morse -l "Soekris rocks" > /dev/led/error +.Ed +.Sh SEE ALSO +.Xr morse 6 +.Sh HISTORY +The +.Nm +driver first appeared in +.Fx 5.2 . +.Sh AUTHORS +.An -nosplit +This software was written by +.An Poul-Henning Kamp +.Aq phk@FreeBSD.org . +.Pp +This manual page was written by +.An Sergey A. Osokin +.Aq osa@FreeBSD.org +and +.An Poul-Henning Kamp +.Aq phk@FreeBSD.org . |
