Index:
	01 - Introduction & Camera Specific Notes

	02 - Installation

	03 - FAQ

	04 - Links, Urls

	05 - GPL, License

	06 - uBASIC copyright notice


************************************


01 - Introduction

Hi, 

this is the small readme to CHDK. It provides just enough info to get you rolling, for more information use the links in the bottom.


CHDK is a firmware enhancement that operates on a number of Canon Cameras. CHDK gets loaded into your camera's memory upon bootup (either manually or automatically). It provides additional functionality beyond that currently provided by the native camera firmware.

CHDK is not a permanent firmware upgrade: you decide how it is loaded (manually or automatically) and you can always easily remove it. 

Main features:

    * Save images in RAW format
    * Ability to run "Scripts" to automate the camera
    * Live histogram (RGB, blended, luminance and for each RGB channel)
    * Zebra mode (blinking highlights and shadows to show over/under exposed areas)
    * An "always on" full range Battery indicator
    * Ability to turn off automatic dark-frame subtraction
    * a higher compression movie mode, and double the maximum video file size
    * exposure times as long as 65 seconds
    * exposure times as little as 1/10,000 of a second
    * ability to use the USB port for a remote trigger input 

Additional features:

    * a depth-of-field (DOF)-calculator
    * File browser
    * Text reader
    * Calendar
    * Some fun tools and games 

Why would I want to use CHDK?

    * To get Raw file capability on cameras that don't have that ability
    * To get the ability to use scripts
    * to be able to know the battery status at all times (not just when it's about to run out of power)
    * you want or need any of the other enhancement features that CHDK provides 

What are scripts? Scripts are Lua or uBASIC language programs that give you the ability to control the operation of the camera under program control. They have been used to add or extend the native capability of the camera: more flexible intervalometers, extended-range exposure compensation, extended bracketing ability, lightning photography, etc. See the script pages for more details.


*** Build Information ***
CHDK for ixus900_sd900 fw:100c PID:12565
build:1.7.0-6343 date:Sun, 21 Sep 2025 04:52:55 +0200

*** Camera specific notes ***
--- CHDK Canon IXUS 900 Ti / Powershot SD900 / IXY Digital 1000 Port -------------------
Camera:     Canon Powershot SD900 (North America/outside Europe) / IXUS 900 Ti (Europe) / IXY Digital 1000 (Japan)
Firmware:   1.00C
Author:     pixel::doc (http://pixeldoc.kicks-ass.net/)
P-ID:       0x3115 (12565)
OS:         VxWorks
Based on Canon IXUS 850IS / SD800 source from chdk trunk.


--- Note ------------------------------------------------------------
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE,
TITLE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE
BE LIABLE FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Software or Author are not affiliated in any way with Canon INC.
Product and Company names mentioned herein may be the trademarks of their respective owners.


--- Links -----------------------------------------------------------
* http://chdk.wikia.com/
* http://chdk.wikia.com/wiki/SD900


--- Developer Stuff --------------------------------------------------
* Rom Start address: 0xFF810000
* CPU: Juno - ARM946ES (ARM)
* OS: VxWorks


--- Changelog -------------------------------------------------------
* 24-Oct-2010: SD900 sources are in the official CHDK trunk since #959, the Autobuild Server delivers the latest binaries.
* Beta v24 (2010-09-26)
    * trunk: #946
    * version: 0.9.9
    * keyboard stuff changed (using kbd_read_keys() from canon firmware)
    * kbd.c added feather task suspend (now feather task is disabled in ALT mode -> does not overdraw chdk anymore)
    * camera.h updated (SD override reenabled)
    * minor improvments

* Beta v23 (2010-08-17)
    * trunk: #920
    * version: 0.9.9
    * CAM_MULTIPART enabled (mount.c)
    * CAM_CONSOLE_LOG_ENABLED enabled (chdklog.txt, stdout.txt, romlog.txt)
    * camera.h defines updated
    * minor improvments

* Beta v22 (2010-08-12)
    * trunk: #919
    * version: 0.9.9
    * fixed source to compile against recent trunk
    * multi partition Support still disabled ("CAM_MULTIPART 1" does crash camera)

* Beta v21 (2009-03-12)
    * trunk: #718
    * version: 0.9.7
    * set_backlight script command FIXED

* Beta v20 (2009-02-14)
    * trunk: #708
    * RAW hook FIXED
    * minor changes

* Beta v19 (2009-02-01)
    * trunk: #701
    * crash in movie mode (bitrate setting) FIXED
    * EnterToCompensationEVF & ExitFromCompensationEVF ADDED
    * compiled with gcc 4.3.2 (chdk-shell 2.0)

* Beta v18 (2009-01-14)
    * trunk: #678
    * AV display (F stop) FIXED (values for auto nd filter corrected)

* Beta v17 (2009-01-09)
    * trunk: #673
    * AV display (F stop) CHANGED
    * reenabled sd override FIXED
    * disabled mf (sd series does not support mf) CHANGED
    * Custom Auto ISO does work TESTED
    * SD overrides does work TESTED

* Beta v16 (2009-01-05)
    * trunk: #666
    * mode map changed FIXED
    * various changes
    * Fast EV Switching (canon menu is not disabled, so currently not very usefull yet) CHANGED
    * MF does not work ToDo
    * Custom Auto ISO does not work ToDo

* Beta v15 (2009-01-03)
    * crash in movie mode with advanced settings FIXED
    * zoom in video mode ADDED
    * AV / TV Value display ADDED
    * log CHANGED
    * MF does not work
    * EV "quick change" does not work
    * various changes

* Beta v14 (2008-12-31)
    * log CHANGED
    * crash in movie mode (advance video settings disabled) FIXED
    * various changes

* Beta v13 (2008-12-30)
    * RAW support ADDED (first RAW image may be corrupted)
    * CRW support does not work yet, badpixel.lua still does not finish correctly (only create file "CHDK\bad_tmp.bin")
    * modemap FIXED
    * movie_mode FIXED
    * after trying to record video, camera does lock up (only CHDK menu work)
    * Debug Log added. If your Camera crashed while using CHDK, look at "stdout.txt", "chdklog.txt" and "romlog.txt" on SD-Card (you can use my added menu items in Debug menu) and add log content to your post.
    * Debug Menu Entries to view log files ("stdout.log", "chdklog.txt", "romlog.txt") added
    * various changes

* Beta v12 (2008-12-28)
    * trunk: #654
    * capt_seq.c FIXED
    * movie_rec.c FIXED
    * shutdown in movie mode if you try to record movie ToDo

* Beta v11 (2008-12-28)
    * trunk: #649
    * chdk works in play, photo and video mode
    * scripts like llibtst.lua OK
    * Zebra OK
    * Histogram OK
    * RAW disabled
    * capt_seq_hook() & movie_record_hook() still disabled in main.c
    * Jogdial / Feather Key symbol gets displayed over chdk menu (feather stuff not ported yet) ToDo
    * movie mode info overlay window is displayed in all modes any time ToDo
    * battery level not correct ToDo
    * sometimes does not boot or shutdown ToDo

* Beta v6 - v10 (2008-12-XX)
    * BIG thanks goes to reyalP for some hours of help und "remote" debugging!

* Beta v1
    * chdk boot not completly and flashes every led in a loop
    * boot.c working

--- ToDo -----------------------------------------------------------
* CAM_MULTIPART (mount.c) does crash camera
********************************

02 - Installation

To install CHDK on your Canon P&S camera,  you need to know the model number and firmware version of your cameras in order to get the right version of CHDK for your camera  Details on how to determine this can be found here :

http://chdk.fandom.com/wiki/Downloads


Once you have the correct CHDK installation file for your camera,  you need to prepare and load your camera's SD card with CHDK.  The best method for doing this depends on how you intend to use your camera and the date your particular carmera was released.  Details can be found here :

http://chdk.fandom.com/wiki/Prepare_your_SD_card

Once you have correctly loaded CHDK,  you can refer to the following section for instructions on how to use CHDK.

****************************************

03 - FAQ

1. What is CHDK?

    CHDK is not just one thing! The term CHDK refers to free software currently available for many (but not all) Canon PowerShot compact digital cameras that you can load onto your camera's memory card to give your camera greatly enhanced capabilities. 

2. Am I likely to be interested in CHDK?

    The enhanced capabilities that CHDK provides are most likely to be of interest to experienced photographers - if you believe that your Canon PowerShot camera already has more features than you will ever need, you probably won't be interested in CHDK. 

3. Is CHDK safe to use?

    Yes CHDK is experimental and has risks, but with tens of thousands of happy users it can generally be considered safe. CHDK doesn't make any actual changes to your camera. If you delete the CHDK software from your memory card, or if you choose not to activate the CHDK software on the card (or remove and replace the batteries), then the camera will behave absolutely normally - nothing has been (or ever is) changed, so the warranty is not affected. 

4. How does CHDK work?

    CHDK makes use of the microprocessor that controls the camera (every digital camera contains a microprocessor) to act as a programmable computer that provides the extra capabilities. 

5. What extra capabilities does CHDK provide?

    The current set of extra capabilities fall into six categories:

        a. Enhanced ways of recording images - you can capture still pictures in RAW format (as well as JPEG), and for video images you can have increased recording time and length (1 hour or 2 GB), and a greatly increased range of compression options. 
        b. Additional data displays on the LCD screen - histogram, battery life indicator, depth of field, and many more. 
        c. Additional photographic settings that are not available on the camera by itself - longer exposure times (up to 65 seconds), faster shutter speeds (1/25,000 sec, and faster in some cases), automatic bracketing of exposure, etc. 
        d. The ability for the camera to run programs ('scripts', written in a micro-version of the BASIC language) stored on the memory card - these programs allow you to set the camera to perform a sequence of operations under the control of the program. For example, a camera can be programmed to take multiple pictures for focus bracketing, or take a picture when it detects that something in the field of view moves or changes brightness. 
        e. The ability to take a picture, or start a program on the memory card, by sending a signal into the USB port - you can use the USB cable to take a picture remotely. 
        f. The ability to do a number of other more useful (and fun) things, such as act as a mini file browser for the memory card, let you play games on the LCD screen, etc. 

6. What else should I know?

    Developers around the world are continuing to add new features to CHDK. Because the idea of using the camera's microprocessor is so flexible, various developers have made different versions of CHDK, and new features continue to be developed - for example, one version of CHDK has features assist in taking stereo photographs, and even allows two cameras to be synchronized to take pictures at the same time (with an accuracy of better than 0.1 milliseconds, providing they are the same camera model). 

The best place to find out more about CHDK is to follow the CHDK wiki  ( http://chdk.fandom.com/wiki/CHDK ) and CHDK user forum ( http://chdk.setepontos.com/ ).




********************************

04 - URLs, Links


For more information visit the following links:

CHDK Forum :                    http://chdk.setepontos.com/index.php

CHDK Wiki:                      http://chdk.fandom.com/wiki/CHDK
CHDK Wiki FAQ:                  http://chdk.fandom.com/wiki/FAQ

CHDK Features :                 http://chdk.fandom.com/wiki/CHDK_User_Manual#Introduction
CHDK in Brief :                 http://chdk.fandom.com/wiki/CHDK_in_Brief
CHDK User Quick Start Guide :   http://chdk.fandom.com/wiki/CHDK_User_Quick_Start_Guide.pdf
CHDK User Manual :              http://chdk.fandom.com/wiki/CHDK_User_Manual
CHDK for Dummies :              http://chdk.fandom.com/wiki/CHDK_for_Dummies
CHDK Installation Guide :       http://chdk.fandom.com/wiki/File:CHDK_Installation_Guide.pdf

One Page Users Guide :          http://chdk.fandom.com/wiki/One_Page_Ultra-Quick_Users_Guide

Prepare Your SD Card :          http://chdk.fandom.com/wiki/Prepare_your_SD_card




*********************************

05 - GPL


/*
 * This file is part of CHDK.
 * Copyright (C) 2008 The CHDK Team
 * CHDK - CHDK Wiki
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA,
 * 02110-1301  USA
 */

*********************************

06 - uBASIC copyright notice

CHDK contains a modified version of Adam Dunkels uBASIC. 

The following notice applies to the original uBASIC code:

Copyright (c) 2006, Adam Dunkels
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.
3. Neither the name of the author nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.

