A3400IS dump

I've dumped the firmware for my A3400IS and it's available here:

http://dl.dropbox.com/u/11452962/PRIMARY.BIN

ff88130c Firmware Version 1.01
ff881328 Firmware Ver GM1.01A

ffc32f47 JN B
ffc3316c Copyright (C) 1997-2011 by CANON Inc.
ffc331f0 DRYOS version 2.3, release #0050

Note that I could not get the firmware version displayed using the Set+Disp buttons. I've tried multiple times with ver.req and vers.req, but nothing worked and the display didn't show. I'm wondering whether this may also impact getting access to the CHDK menu.

Instead, there was a file on the sd-card in the MISC directory with these contents:

{
"info version":"1.0",
"firmware version":"HD2.08.12.70",
"camera type":"HD2",
}

Note that I could not get the firmware version displayed using the Set+Disp buttons. I've tried multiple times with ver.req and vers.req, but nothing worked and the display didn't show. I'm wondering whether this may also impact getting access to the CHDK menu.

I had the same problem with a810 and a2300 (cameras released in 2012).  But it does not have any impact to get access to CHDK menu, during the port you select the button to access chdk menu, commonly playback [>]  button is used.