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Camera technical data

Release date:August 2007
Sensor CCD size:8.0 MP 1/2.5"
Lens (35mm equiv) zoom35-210, 6x
LCD size2.5" fixed
CardSD / SDHC / MMC
Size (mm)96.5 x 66.0 x 43.2
Weight (body)200 g


Inside this decent camera, the OS is the new DryOS, see also DryOS Porting.

Firmware info

Firmware information is given if ver.req exists on the SD.

In PLAY mode (with ver.req) press FUNCSET and DISP simultaneously:

Canon PowerShot A720 IS
P-ID:315D  PAL D

Firmware Ver GM1.00C
E18
Jul  5 2007 11:32:58

Subsequent press of DISP (while still holding FUNCSET) reveals:

Adj Ver.012.006
ZoomLensError
2007.10.22 00:41:26

After another subsequent press of DISP (while still holding FUNCSET) reveals:

Adj Ver.012.006
IS Firm Ver.  3.00
IS Param Ver.  3.11

Firmware Dump

Firmware extraction using the blinker was some trouble but worked.

Here is the file: A720IS-100c.zip

Since no "update firmware" menu entry is available, this method could be used.

Instead a "bootable" SD and "diskboot.bin" can be used to run the blinker.

LED memory adresses

 #define AF 0xC02200c0    // AF-Beam (red)
 #define DP 0xC02200c4    // direct-print (blue)
 #define OR 0xC02200c8    // orange state-led (bi-state with green)
 #define GR 0xC02200cc    // green state-led (bi-state with orange)
 #define YE 0xC02200d0    // Yellow state-led
 #define PW 0xC02200d4    // Power (green)

Current Status

Canon switched the OS from VxWorks (used on earlier cams) to their own DRYOS with the A720. That means that a lot of reverse engineering has to be done to find out how to hook an extension like CHDK into the A720. See dpreview-posting and Canon page on DRYOS

Most of the porting work is nearly done! Check here for the Current Status

A (nearly) complete port of Allbest's branch is finished. Only few features are missing, such as

  • usb-support for remote shooting
  • long filename support in filemanager

You need to:

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