Need Help accessing i2c EEPROM using a RasPi

[Georgy05]

I want to edit the contents of a chip on my Notebook.
I am trying to read out the contents of an i2c ROM that's a NXP P24S08A.

Following along with resources online I got as far as trying the "i2cdetect" command on my Raspberry Pi. On my first try it read nothing.


I tried again and tried "To find the address of your i2c slave device." https://payatu.com/using-rasberrypi-as-p...cking-tool
This is what I got:


It looks like success - it's reading something. But I don't really know what I'm doing, and now I'm basically stuck.

I'll follow up with a post of why I'm doing this and what I've done already. The short version is:
I believe that my Lenovo Thinkpad S1 has a security password after after the supervisor password was entered wrong too many times. I believe this password to be on the Security Chip which should be this NXP P24S08A.

I have found a schematic of my motherboard which is why I believe this (however this is all new to me, and I don't trust myself to know what I am doing). Very much hoping to learn through the help of other's more knowledgeable on this forum.

Who has tried to access a security chip ROM that communicates over i2c and can tell me how to continue??

[Georgy05]

My Notebook I am trying to fix:
Lenovo Thinkpad Yoga S1 20C0 (i5, 8GB RAM)

My Problem:
I bought my Notebook of eBay 2nd hand, and I sadly had to find out that it had a Supervisor Password set. Very foolishly the supervisor password was entered wrong too many times (3 times).
Now upon switching on the Notebook, it immediately asks for a password, before a flash screen or booting or anything else (besides displaying error messages if for example I disconnected all the batteries).
The password it asks for shows a person next to a lock.

In the following thread it is described as a Supervisor Password by rumpumpel1
https://www.bios-mods.com/forum/Thread-Q...-removable

What I have done:
So far I have managed to read read the BIOS ROMs using a raspi + SOIC 8 clip and flashrom. I have flashed these ROMs with backups I have made from another Yoga S1 which had no BIOS passwords. This doesn't change anything.

I have found a schematic online for my motherboard and I have found a datasheet for PCA24S08A 1024x8-bit CMOS EEPROM with access as protection, as well as a datasheet for an Amtel AT24RF08C.

The the U11 chip on my motherboard is a NXP P24S08A.

What I have tried:
I tried removing all batteries (laptop Battery removed and disconnected CMOS battery).
I tried shorting the SCL and SDA pins.


What I believe I need:
I need to null the Security password on the Security chip (P24S08A).

[Georgy05]

The eBay seller didn't know the password. He sold me a working Notebook. It's only when I tried to enter the BIOS to activate the virtualisation feature of the CPU that I realised I couldn't change any BIOS settings.


After removing all the batteries I get the following displayed after turning the Notebook on:
0251: System CMOS Checksum bad - Default configuration used.
0199: System Security - Security password retry count exceeded.
Real Time Clock Error - Check Date and Time settings

Press F1 to enter Setup.

>after pressing F1 it asks for the password with the pictogram of a person next to a lock.



About shorting the SCL and SDA pins. I tried this last year. May be I failed to this this properly. I did not have a soldering kit to solder on wires, so I had used two probes latched on to the SCL and SDA pins each with a wire attached.
When the motherboard is connected to the monitor and the rest of the notebook, the P24S08A ROM is on the side of the access and inaccessible. That is why I do not know if I had good contacts.

Summary:
After trying those things last year I accepted that my laptop was bricked and put the brick into my wardrobe until such a day as I might have the proper hardware to fix it.

Now with the COVID-19 pandemic and shelter-in-place/lockdown, I can't do much. I have grabbed the tools I have and am trying to fix my Notebook again. It's a very expensive brick you see  

The only tools at my disposal - my ancient Sony Vaio running Ubuntu 14.04, a Raspberry Pi, a breadboard, a SOIC 8 clip, some probes and some wires...
#FixAtHome

[Georgy05]

I meant to put this in the General Help section .....I think I'm too tired. Please advise me on all I did wrong
-be it by posting in the wrong section
-a suggestion for a better thread title
-information that's missing

Thank you

[Georgy05]

I've finally fixed my laptop! 


....with a simpler method. I was able to reset my BIOS passwords by shorting pins 5 and 6 on the NXP P24S08A (security chip?)


Like in the following link:
http://kinggeek.co.uk/tech-notes/item/46...r-own-risk

[kzmudzi]

I've finally fixed my laptop! 


....with a simpler method. I was able to reset my BIOS passwords by shorting pins 5 and 6 on the NXP P24S08A (security chip?)


Like in the following link:
http://kinggeek.co.uk/tech-notes/item/46...r-own-risk

thank you very much for this, was able to remove administrator password on my s1 yoga. took 10 minutes to do and didnt have to pay a cent