Service Forum

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

Welcome all ... iam supervisor password locked notebook Thinkpad 765D with STC46CM1 and near Maxim MAX3243CA ...will work this guide ?

bob · Posted: Tue Dec 30, 2008 11:47 pm Post subject:

STC46 is 93C46 - that't the one.

The method is the same but not the software and is not working with siprog exactly as it is, needs 1diode + 1 resistors extra. Read this:

http://www.allservice.ro/forum/viewtopic.php?t=200&highlight=765d

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

thanks ... must i unsolder the eeprom chip ?? or suffice provide scheme without power supply (suppy will provide powered on notebook)

i have three 5,6 V zeners at home .. can i use this instead 5,1V used in scheme ?

laptopheaven · Nou Venit Joined: 27 May 2008 Posts: 7 Location: Hamburg

Hi ravenman,

normally you don't have to unsolder the chip.
Just use fine probes or needles to contact the chip.

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

can i use a 5V1 zener diode instead 5V6 ?

victor · S.F. Boss Joined: 07 Mar 2004 Posts: 2581 Location: Staff

No, use 5V1
_________________
Victor Voinea
ALLservice HQ, Romania.

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

okey aim finished a circuit ... tested with "itester" SDAin/SDAout and i see 1 for each value .. this is ok , but when i wrote "r24rf08.exe myibm" program warn me abou this

Initializing timer 17208 OK
ERROR: Circuit not found or bus error ...

and PONYPROG reads my eeprom and i see anywhere zeros

why ?? very thanks

[

bob · Posted: Tue Jan 06, 2009 1:08 pm Post subject:

itester is not made for this circuit and R24RF08 is also made for other kind of eeprom! Why in the world would you do that Rolling Eyes

Unsolder the 93C46 if you want to read with PonyProg w/o problems. Pony must be calibrated and select Microwire16 - 9346.

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

okey aam going probe now ... and then i unsolder the eeprom can i connect all COM pins same time to COM or must connect first GND , ,second SDA , SCL .. and other pins ?

ravenman · Interesat Joined: 30 Dec 2008 Posts: 12

i am broke a COM/GND leg in eeprom chip ..its possible read a content of chip without this leg (number 5) ? or no its really use chip back in laptop whithout leg ?

very thnx for your professional advices

victor · S.F. Boss Joined: 07 Mar 2004 Posts: 2581 Location: Staff

Pin#5 is the ground, if broken the eeprom is not powered.
Try to solder a piece of enamel coated wire to the remaining part.
If you still can't solve this, you may send the eeprom to us and we will recover the content and write into a new chip.

Or I could simply mail you a pre-programmed clean eeprom to replace the damaged one (this will be for free, but the beers are on you). The original serials will be lost and of course the password will remain unknown Laughing

_________________
Victor Voinea
ALLservice HQ, Romania.