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LCDd

LCDd

Section: LCDproc suite (8) Updated: 14 May 2009
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NAME

LCDd - LCDproc server daemon

 

SYNOPSIS

LCDd [-hf] [-c config] [-d driver] [-i bool] [-a addr] [-p port] [-u user] [-w time] [-r level] [-s bool]

 

DESCRIPTION

LCDd is the server part of LCDproc, a deamon which listens to a certain port (normally 13666) and displays information on an LCD display. It works with several types and sizes of displays.

Most settings of LCDd are configured through its configuration file /etc/LCDd.conf, some of them can be overriden using command line options. Before running LCDd you should carefully read through that file and modify everything neccessary according to your needs. Otherwise you might encounter LCDd not running properly on your system.

To make full use of LCDd, a client such as lcdproc(1), lcdexec(1), or lcdvc is required.

 

OPTIONS

Available options are:
-h
Display help screen
-c config
Use a configuration file other than /etc/LCDd.conf
-d driver
Specify a driver to use (output only to first), overriding the Driver parameter in the config file's [Server] section.
-f
Run in the foreground, overriding the Foreground parameter in the config file's [Server] section. The default, if not specified in the config file, is to daemonize LCDd as it is intended to operate in the background.
-i bool
Tell whether the to enable (1) or disable (0) showing the LCDproc server screen in n the screen rotation, overriding ServerScreen in the config file's [Server] section.
-w waittime
Time to pause at each screen (in seconds), overriding the WaitTime parameter in the config file's [Server] section.
-a addr
Bind to network address addr, overriding the Bind parameter in the config file's [Server] section.
-p port
Listen on port port for incoming connections, overriding the Port parameter in the config file's [Server] section.
-u user
Run as user user, overriding the User parameter in the config file's [Server] section.
-s bool
Output messages to syslog (1) or to stdout (0), overriding the ReportToSyslog parameter in the config file's [Server] section.
-r level
Set reporting level to level, overriding th ReportLevel parameter in the config file's [Server] section.

 

SUPPORTED DRIVERS

Currently supported display drivers include:
bayrad
BayRAD LCD modules by EMAC Inc.
CFontz
CrystalFontz CFA-632 and CFA-634 serial LCD displays
CFontz633
CrystalFontz CFA-633 serial/USB LCD displays
CFontzPacket
CrystalFontz CFA-631, CFA-633 and CFA-635 serial/USB LCD displays
curses
Standard video display using the (n)curses library
CwLnx
serial/USB displays by Cwlinux (http://www.cwlinux.com)
ea65
VFD front panel display on Aopen XC Cube EA65 media barebone
EyeboxOne
LCD display on the EyeboxOne (http://www.rightvision.com)
g15
LCD display on the Logitech G15 keyboard
glcdlib
graphical LCDs supported by graphlcd-base
glk
Matrix Orbital GLK Graphic Displays
hd44780
Hitachi HD44780 LCD displays. This driver supports the following sub-drivers (a.k.a. connection types):
4bit
LCD 4bit-mode, connected to a PC parallel port
8bit
LCD 8bit-mode, connected to a PC parallel port
serialLpt
LCD in 4bit-mode through a 4094 shift register
winamp
LCD in 8bit-mode using WinAmp-wiring, connected to a PC parallel port
picanlcd
LCD driven by a PIC-an-LCD chip/board by Dale Wheat, connected to a serial port
lcdserializer
LCD driven by a PIC16C54-based piggy-back board, connected to a serial port
los-panel
LCD driven by an Atmel AVR based board, connected to a serial port
vdr-lcd
???, connected to a serial port
vdr-wakeup
VDR-Wake module by Frank Jepsen (http://www.jepsennet.de/vdr/)
pertelian
Pertelian X2040 module (http://pertelian.com/)
lis2
LIS2 from VLSystem (http://www.vlsys.co.kr), connected to USB
mplay
MPlay Blast from VLSystem (http://www.vlsys.co.kr), connected to USB
bwctusb
USB-to-HD44780 converter by BWCT (http://www.bwct.de)
lcd2usb
Till Harbaum's open source/open hardware LCD2USB (http://www.harbaum.org/till/lcd2usb/)
uss720
USS-720 USB-to-IEEE 1284 Bridge (Belkin F5U002 USB Parallel Printer Adapters)
i2c
LCD in 4-bit mode driven by PCF8574(A) / PCA9554(A), connected via I2C bus
ftdi
USB connection via a FTDI FT2232D chip in bitbang mode
ethlcd
TCP connection using open source/open hardware ethlcd (http://manio.skyboo.net/ethlcd/)
usblcd
LCD device from Adams IT Services (http://www.usblcd.de/)
i2500vfd
140x32 pixel VFD Display of the Intra2net Intranator 2500 appliance
icp_a106
ICP A106 alarm/LCD board in 19" rack cases by ICP
imon
iMON IR/VFD modules in cases by Soundgraph/Ahanix/Silverstone/Uneed/Accent
imonlcd
iMON IR/LCD modules in cases by Soundgraph/Ahanix/Silverstone/Uneed/Accent/Antec
irtrans
IRTrans IR/VFD modules in cases by Ahanix (e.g. MCE303) and possibly others May require irserver (http://www.irtrans.de/en/download/linux.php) to be running for connectivity.
IOWarrior
Code Mercenaries IOWarrior
irman
IrMan infrared (input)
joy
Joystick driver (input)
lb216
LB216 LCD displays
lcdm001
kernelconcepts.de 20x4 serial LCD displays
lcterm
serial LCD terminal from Helmut Neumark Elektronik (http://www.neumark.de)
lirc
Infrared (input)
lis
L.I.S MCE 2005 20x2 VFD (http://vlsys.co.kr)
MD8800
VFD displays in Medion MD8800 PCs
ms6931
MSI-6931 displays in 1U rack servers by MSI
mtc_s16209x
MTC_S16209x LCD displays by Microtips Technology Inc
MtxOrb
Matrix Orbital displays (except Matrix Orbital GLK displays)
mx5000
LCD display on the Logitech MX5000 keyboard
NoritakeVFD
Noritake VFD Device CU20045SCPB-T28A
picolcd
Mini-box.com USB LCD (PicoLCD 20x4 & picoLCD 20x2)
pyramid
LCD displays from Pyramid (http://www.pyramid.de)
sed1330
SED1330/SED1335 (aka S1D13300/S1D13305) based graphical displays
sed1520
122x32 pixel graphic displays based on SED1520 controllers
serialPOS
Driver for Point Of Sale ("POS") devices using various protocols (currently AEDEX only)
serialVFD
Text VFDs of various manufacturers, see LCDproc user-documentation for further details.
shuttleVFD
Shuttle VFD (USB-based)
sli
Wirz SLI driver (unknown)
stv5730
STV5730A on-screen display chip
svga
VGA monitors using svgalib
t6963
Toshiba T6963 based LCD displays
text
Standard "hard-copy" text display
tyan
LCD module in Tyan Barebone GS series
ula200
ULA-200 device from ELV (http://www.elv.de)
xosd
On Screen Display on X11

Multiple drivers can be used simultaneously; thus, for example, a Matrix Orbital display (MtxOrb driver) can be combined with an infrared driver (irmanin driver).

 

INVOCATION

LCDd -d MtxOrb -d joy
The invocation example above will start LCDd reading its configuration from the default configuration file /etc/LCDd.conf but overriding the drivers specified therein with the Matrix Orbital driver and the Joystick input driver.

 

LCDPROC CLIENT-SERVER PROTOCOL

There is a basic sequence:
1. Open a TCP connection to the LCDd server port (usually 13666).
2. Say "hello"
3. The server will return some information on the type
of display available.
4. Define (and use) a new screen and its widgets.
5. Close the socket when done displaying data.

 

CLIENT COMMANDS

There are many commands for the client to send to the LCDd server:
hello
This starts a client-server session with the LCDd server; the server will return a data string detailing the type of display and its size.
client_set -name name
Set the client's name.
screen_add #id
Add a new screen to the display.
screen_del #id
Remove a screen from the display.
screen_set #id [-name name] [-wid width] [-hgt height] [-priority prio] [-duration int] [-timeout int] [-heartbeat mode] [-backlight mode] [-cursor mode] [-cursor_x xpos] [-cursor_y ypos]
Initialize a screen, or reset its data.
widget_add #screen #id type [-in #frame]
Add a widget of type type to screen #screen.
widget_del #screen #id
Delete widget #id from screen #screen.
widget_set #screen #id data
Set the data used to define a particular widget #id on screen #screen.

 

HEARTBEAT MODES

Valid heartbeat mode values (for the screen_set command) are:
on
Display pulsing heart symbol.
off
No heartbeat display.
open
Use client's heartbeat setting. This is the default.

 

BACKLIGHT MODES

Valid heartbeat mode values (for the screen_set command) are:
on
Turn backlight on.
off
Turn backlight off
toggle
Turn backlight off when it is on and vice versa.
open
Use client's backlight setting. This is the default.
blink
Blinking backlight
flash
Flashing blacklight

 

Priorities

Valid priority settings (used in the screen_set command) are as follows:
input
The client is doing interactive input.
alert
The screen has an important message for the user.
foreground
an active client
info
Normal info screen, default priority.
background
The screen is only visible when no normal info screens exists.
hidden
The screen will never be visible.

For compatibility with older versions of clients a mapping of numeric priority values is also supported:

1 - 64
foreground
65 - 192
normal
193 - (infinity)
background

An example of how to properly use priorities is as follows:

Imagine you're making an mp3 player for lcdproc. When the song changes, it's nice to display the new name immediately. So, you could set your screen's priority to foreground, wait for the server to display (or ignore) your screen, then set the screen back to normal. This would cause the mp3 screen to show up as soon as the one on screen was finished, then return to normal priority afterward.

Or, let's say your client monitors the health of hospital patients. If one of the patients has a heart attack, you could set the screen priority to alert, and it would be displayed immediately. It wouldn't even wait for the previous screen to finish. Also, the display would stay on screen most of the time until the user did something about it.

 

WIDGET TYPES

Widgets can be any of the following:
string
A text string to display (as is).
hbar
A horizontal bar graph.
vbar
A vertical bar graph.
title
A title displayed across the top of the display, within a banner.
icon
A graphic icon.
scroller
A scrolling text display, scrolling either horizontally or vertically.
frame
A container to contain other widgets, permitting them to be refered to as a single unit. A widget is put inside a frame by using the -in #id parameter, where #id refers to the id of the frame.
num
Displays a large decimal digit

Widgets are drawn on the screen in the order they are created.

 

SETTING WIDGET DATA

In the widget_set command, the data argument depends on which widget is being set. Each widget takes a particular set of arguments which defines its form and behavior:
string x y text
Displays text at position (x,y).
title text
Uses text as title to display.
hbar x y length
Displays a horizontal bar starting at position (x,y) that is length pixels wide.
vbar x y length
Displays a vertical bar starting at position (x,y) that is length pixels high.
icon x y name
Displays the icon name at position (x,y).
scroller left top right bottom direction speed text
The text defined will scroll in the direction defined. Valid directions are h (horizontal) and v (vertical). The speed defines how many "movements" (or changes) will occur per frame. A positive number indicates frames per movement; a negative number indicates movements per frame.
frame left top right bottom wid hgt dir speed
Frames define a visible "box" on screen, from the (left, top) corner to the (right, bottom) corner. The actual data may be bigger, and is defined as wid (width) by hgt (height); if it is bigger, then the frame will scroll in the direction (dir) and speed defined.
num x int
Displays large decimal digit int at the horizontal position x, which is a normal character x coordinate on the display. The special value 10 for int displays a colon.

 

BUGS

If LCDd seems not to work as expected, try to run it in the foreground with reporting level set to maximum and reporting to stderr. This can be achieved without changes to the config file by using the command line:
LCDd -f -r 5 -s 0

 

FILES

/etc/LCDd.conf, LCDd's default configuration file

 

SEE ALSO

lcdproc-config(5), lcdproc(1), lcdexec(1)

 

AUTHOR

LCDd was originally written by William Ferrell (wwf@splatwerks.org) and Scott Scriven (scriven@cs.colostate.edu).

Since that time various people have contributed to LCDproc.

The newest version of LCDd should be available from here as part of the lcdproc package:


                http://www.lcdproc.org/

 

LEGAL STUFF

The lcdproc package is released as "WorksForMe-Ware". In other words, it is free, kinda neat, and we don't guarantee that it will do anything in particular on any machine except the ones it was developed on.

It is technically released under the GNU GPL license (you should have received the file, "COPYING", with LCDproc) (also, look on http://www.fsf.org/ for more information), so you can distribute and use it for free -- but you must make the source code freely available to anyone who wants it.

For any sort of real legal information, read the GNU GPL (GNU General Public License). It's worth reading.


 

Index

NAME
SYNOPSIS
DESCRIPTION
OPTIONS
SUPPORTED DRIVERS
INVOCATION
LCDPROC CLIENT-SERVER PROTOCOL
CLIENT COMMANDS
HEARTBEAT MODES
BACKLIGHT MODES
Priorities
WIDGET TYPES
SETTING WIDGET DATA
BUGS
FILES
SEE ALSO
AUTHOR
LEGAL STUFF

This document was created by man2html, using the manual pages.
Time: 22:01:54 GMT, April 16, 2011