Dell 8FC8 Patcher

[larryb01]

Source code.txt (9.3 KB, 1188 views)

Is the source code still available? I'd like to learn more about this process.

[diamon]

Here you go, this is the source code (Python script).

[larryb01]

Thank you!

[rex98]

this is the original source code

[larryb01]

this is the original source code

Thank you! VB.Net will always hold a place in my heart... 😀

[Banagus33]

i succensfully patched my BIOS by myself usig patcher. It was DELL Latitude 5300 NortBay Non-TBT MB A00 18827-1 P3HJY$CA. BIOS has 32 Megabytes single IC.
Thank You

[larryb01]

I've been researching how to dump the BIOS from a Dell 5420. This Youtube video shows the exact model and uses the same chip (W25R256JVEN) as the one I am trying to read. However, I have a few questions before I proceed.

I do not have the funds for a decent hot air station setup, so I will need to read the chip directly on the board. I planned on using a CH341A programmer and the ASProgrammer software. Is this reader and software appropriate?

I did realize that the CH341A programmer package linked above uses a SOIC8 clip but since the chip package is WSON8, I will need this probe attachment in 8x6. I plan to do three full dumps and compare the checksums to hopefully ensure a good dump.

In ASProgrammer I found the chip "W25R256JV" which I assume will work for the W25R256JVEN variant. The data sheet says that it is 3V and ASPRogrammer did not denote 1.8V like it does for other chips. Is that correct? Does it matter that the chip in ASProgrammer doesn't end in "EN"?

I appreciate any help you can give and I realize I'm asking a lot of questions. 🙂

[larryb01]

I did not see a way to edit my previous post but I will answer my own questions to serve as guidance for others who may wish to perform the same process.

Yes, the CH314A will work to read the firmware from the W25R256JVEN. In the CH314 Programmer v2.21 (by Shichang Zhuo) it will be recognized as a W25Q256FV, but it will read, wipe, and verify fine. However, what will not work, is what I originally tried - running windows in a VM (VirtualBox on Linux) and passing the USB programmer through to the guest OS. This setup never resulted in a good read of the chip so I had to go directly to the hardware running windows.

Also what will not work - if you orient the pins on the WSON probe incorrectly in the ZIF socket on the reader. The part of ZIF (on my reader) with the lever is where pin 1 is located. To read 25 series BIOS chips you need to orient pin 1 correctly and at the bottom of the ZIF socket if you use the same hardware in the link above. Thankfully, the reader is smarter than I am and would reset when incorrectly connected.

I'd love to know more about how someone was able to find the correct sequence of bytes to replace and if/how one could view the assembly of the firmware. Perhaps more to learn in the future.

So, a big thanks to everyone for the help. I learned a lot and bought someone a beer (hopefully.) Cheers!