Service Forum

[coolnyan]

Hi There,

I have IBM Thinkpad R32 and I am trying to unlock BIOS password. The ATMEL chip is 93C46. I follow diagram instruction but when I launch R24RF08 command, I got error message:

"Circuit Data Bus Error or Not Found"

Before I got Circuit error, I got EEprom error. Then I re-solder the wires on ATMEL chip and now I got Circuit error. I also have tried using command R24RF08 /X /D /I or run PATCHER.EXE and I still got the same error. I verified that the serial port is working and I even have swap different computer. I got dump.bin file but the size is zero K.

How can I use Multimeter to test if the connection is good and the power required for the EEPROM reader is available? Is there anything that I need to verify besides the power for EEPROM reader?

I appreciate any direction and help on this matter.

Thanks.

[coolnyan]

I check Victor's instruction on post before this:

1. connect the interface to COM1 and let the SDA and SCL wires on the air;
2. Execute the itester.exe and click <connect>. The timer will start and you will see "SDA/SCL out" and SDA in changing values.

First I see "0" values for "SDA/SCL out" and "SDA in", then the value switch together to "1" after 5 seconds, then go back to "0."

I see Victor's instruction on Multimeter so I am off to store now to get one. Please let me know if I should try other things.

Thanks.

[coolnyan]

I check the voltage on SDA and SCL in respect to ground with voltmeter and the value looks correct:
SDA (1) = 4.9V
SDA (0) = -0.6V
SCL (1) = 5.1V
SCL (0) = -0.6V

It looks like the EEPROM reader works correctly. I even rebuild the reader with new components but still got the same error.

How can I check if the ATMEL chip itself works fine?

Is it possible because the ATMEL chip is 93C46 that I need to use different software?

Thanks.

[richk]

If I remember correctly, R30 uses a regular 8-pin R24RF08. It is under the PC card cage and under a black plastic sheet. You need only to remove the keyboard, palmrest and PC card cage.

[victor]

You can't use R24RF08 to read 93C46, that is not even a I2C eeprom!
And Richk is right, R32 uses an 8 pin 24RF08 as well as all the other TPs in its generation.

Here is the 24RF08 eeprom
_________________
Victor Voinea
ALLservice HQ, Romania.

[coolnyan]

Richk and Victor,

You guys right! I soldered the wrong CHIP! I don't know there are more than one ATMEL chips on the motherboard. I connect to the correct ATMEL chip and I am able to see the password.

You guys ROCK!

Thanks for your help.