issue with dell latitude 5480 bios rewrite

[reverendalc]

hello badcaps,

once again i turn to you for salvation:

2017 dell latitude 5480 i5

unit had unknown bios pw, and boot from USB protected

i dumped the BIOS with my flashcat and verified the dump against the chip, ok
i prepared a clean ME bios
write of new bios failed, unable to write to chip. erase seems to be functioning?
i opened original dump of bios (which verified against chip) and it's mostly zeroes?? like 99% zeroes, one little header and one little block of data halfway through.

flashcat can only see the chip if battery&AC are removed.
ch341a (flashrom, ubuntu) can see the chip with battery&AC connected but cannot write either
ch341a with AsProgrammer (win10) seems to identify, read/write/erase with no issue, as well as verify.

attached is the clean dump i am writing.

welcoming all ideas/bios dumps/etc.

cheers

[ktmmotocross]

Re: issue with dell latitude 5480 bios rewrite

did u check datasheet of bios ic that it is not 1,8V ic?

if it is not than replace ic

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

chip is 3.3v W25Q128FV

why do you think IC is bad? i've handled an unfathomable amount of bricked BIOS laptops and only twice had to replace IC.

additionally, when cleaning ME of internet dump;

ME analyzer reports 11.6.1.1142 corp H and the ME from the repo is 7176kb
when i decompose the bios, the ME region is only 6156kb
if i decompose the ME from the repo, there is a 6352kb ME Region inside

i'm super confused

[khaahk]

Re: issue with dell latitude 5480 bios rewrite

Desolder and read-erase-write?

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

i'm not sure that I have a good BIOS to write at this point...

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

Try the one at post #29 .You`ll have to clean the ME though .
https://www.badcaps.net/forum/showthread.php?p=818840

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

sweet thanks! i searched forum for 5480 but nothing came up.

writing now

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

sweet thanks! i searched forum for 5480 but nothing came up.

writing now

When searching keywords use * , *5480*

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

that dump says board LA-E082P and my board reads E081P.

should still work? in my excitement i forgot to clean ME lol. will report back.

ME Analyzer spits out a TON of errors when analyzing that dump from post#29

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

trying to clean ME on this as well, i do not understand:

ME region from repo is different size than ME region from decomp?
after decomposing ME from the repo, even the ME inside is the wrong size.

MEAnalyzer reports 11.8.55.3510 corp lp C NPDM PRD RGN

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

Yes the ME is broken, i did try to fix that in another post,i forgot all about it. https://www.badcaps.net/forum/showthread.php?t=73802
Do you have the service tag number .

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

will peruse that post.

servicetag is H9FMBH2

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

same issue as murtaza527, absolutely no response to power button with that dump

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

Ok ,by your service tag you have a configuration without VPro/AMT (631-ABEI : No Out-of-Band Systems Managem ent), thats why the bios i posted to won`t work. EDIT: Your original bios dump should be ok with the same ME from the repository, or update to 11.6.29.3287_COR_H_D0_PRD_RGN.bin .As for updaing/merging the bios,the latest one Latitude_5X80_Precision_3520_1.14.2.exe once extracted only has VPro ME updates, so look for the same bios version as your dump or the last one that included a COR_H_D0_PRD_RGN.bin

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

crab nuggets. i guess i could just spend $25 buying every dump on ************ and crossing my fingers?

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

Try this one,based on your dump, i `m not sure if this one will work,boot guard seems wrong . If you have an unmodded dump before you cleaned the ME - post it .

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

i'll try that shortly. here's my original dump, but i strongly believe it was compromised despite verifying against the chip afterwards.

haha it compressed to less than 100kb. definitely was botched.

[SMDFlea]

Re: issue with dell latitude 5480 bios rewrite

i'll try that shortly. here's my original dump, but i strongly believe it was compromised despite verifying against the chip afterwards.

haha it compressed to less than 100kb. definitely was botched.

I meant your first full 16MB backup,before you cleaned the ME

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

the original bios which i failed to backup correctly...
the first bios i attached, downloaded from ************ was already "cleaned"

that's why i mentioned not being sure i have a working bios to play with

[reverendalc]

Re: issue with dell latitude 5480 bios rewrite

i am beginning to believe that i am not correctly writing to this chip. my flashcat will only detect the chip with no battery or wall power connected, but it cannot write to the chip as such. one time i powered on the laptop (on battery), then pressed and held the power button until it shut off, continued holding the power button, and the flashcat both saw and wrote to the chip. didn't seem to work though.

my ch341a will detect the chip with power connected, and will write to it, but the dump won't verify against the chip contents afterwards.

i've tried my flashcat in win10, my ch341a in win10 and ubuntu as well.

also, sometimes the flashcat says the chip is detected but not found in library.

what gives? usually these dells are easy on easy off.