BIOS Modders who are up for a challenge

[Freak4915]

Dear Bios mods,

I have an interesting one. I have a hobby of purchasing proprietary firewall boxes and stripping them a part and unlocking there secrets with the end goal of getting it to run other code. My most recent purchase has been the most well defended a SonicWall sra 4200. It runs under a VIA x86 CPU with an custom AMI Bios base.

Was able to get to the stage of stripping the BIOS from the chip and load it up with AMIBCP 3.13.

Even though the quick and quiet boot options are set to disabled and the hit 'DEL' display message is enabled. Mashing DEL at the start doesn't get me into the BIOS. The only options I have is F11 which enables me to select boot device, without the enter setup option.

The boot sequence comes across as though the normal boot screen in which the bios does an integrity check of the available memory and detection of drives is missing, in which you'd only get the usual boot beep, and straight into the booting of the onboard CF card.

There was a module which I had never seen before called "secure CF" which I'm sure is proprietary to SonicWall which after the first install onto the CF locks the card to the unit. As taking out the CF is unreadable on any computer even though it appears to be a FreeDOS entry point being palmed of to a linux boot manager after verification.

If anyone could shed some light on why/how the entry to the BIOS has been disabled, or what purpose does the secure CF module play would be great. Happy to answer any questions. I have little modding experience so either I just missed something very simple and this will be solved within seconds, in which I'm sorry or actually be a little bit of fun for someone to get around. I know I will be. Thanks in advance.