hi
i need some help locating the eeprom on the circuit board shown below.


that circuit board is from a Li-Ion battery used for the psp.
Once i find the eeprom, i need to pull out the GND pin from it so that the eeprom is disabled and so the microcontroller returns a serial number of 0xFFFFFFFF to the PSP, which then goes into service mode. Once in service mode i can install custom firmware on to the psp.

thanks in advance.

 

Looks like the chip on the very left. Google the part number to find out which one is the GND leg (and to be sure it is an EEPROM).

 

thats the thing, i tried to google the chip earlier with no success!
this is whats written on the top of that 8 leggi --> 9926delta7K4H

the delta isn't a word, its printed as a symbol.

 

Hi,
Just cutting the 'ground' pin of the EEprom will leave the the data/clock floating?

Cant you just remove the EEprom or cut the data/clock pcb track, then ground or pull high these two lines to the controller?

The number you quoted is most likely a PSP 'house' type number.

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

yep, cutting the track seems to be a safer idea...
but how do i identify the GND pin so that i can cut the track following its route alone

 

It should be possible to identify the ground/0v pin using a DVM.

Do you guidance on how to do that.?

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

yes very much

 

OK,
Can you post a picture of the other side of the pcb?
I will try to indicate on the pictures the best way to use the DVM.

__________________
Eric
"Good enough is Perfect"

PIC tutorials:
Gramo's: www.digital-diy.net/
Bill's: www.blueroomelectronics.com/

 

ok the one shown above is pretty much busted by now(tried some unorthodox bullshit)

i do have another battery and i'm looking forward to do the same thing with it too( i mean deactivating the GND of eeprom)

here are the pics



now you can see that the pin is already removed and also i smoked it aswell! but that's alright as it didn't cost too much....i need some practice with this before i get another one

 

I'd guess pin 1, in the bottom left, since its hooked up to that big plane. Hook up a DMM between a known ground plane and pin 1, and see if you get any voltage reading - if you do, its not ground, if you get 0v, its ground.

And guys, he's looking to remove the leg to get the PSP into recovery mode, but if you cut the trace, youre going to have to fix it. Seems easier to take the chance and lift the leg, since its a lot easier to put back.

 

actually cutting the trace is a lot easier (and safer from my personal experience) since we can retrace it with any lead pencil.

ok thanks with all that help, i guess now i know how to figure out the GND pin
but it doesn't end there.....i'd like to know how to identify the particular eeprom to be modified on any psp compatible battery so that i don't have to look all around the country for an original battery from sony

 

I personally feel safer lifting the leg than cutting traces but thats just me.

As for modifying the EEPROM, I dont think anyone here would be able to help you. You need to have someone dump the EEPROM and decrypt it to know what everything means. Id try a site like psphacks.com

The people here could probably tell you how to remove the chip or read it while its on the board, and program it, but I doubt they know much about PSP Hacks

EDIT And why is it so hard to find an original battery? I can go to walmart or Zellers or Gamestop or Futureshop or Best buy... you get the picture, and get a battery.