Service Forum

carl0s · Nou Venit Joined: 17 Jan 2006 Posts: 7

Does there look to be anything wrong here? I haven't got the SDA/SCL/GND wires coming off it yet, as I'm not finished and it's bed time.
It seems strange that I'm putting all the power directly into that capacitor.
Also, my 232 IC is a MAX232CPE, does this mean I should use the 1uf capacitors, or the 0.1uf? I have used 0.1uf for now..

thanks Smile

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

Yes, you have to use 1uF.

carl0s · Nou Venit Joined: 17 Jan 2006 Posts: 7

Help! It doesn't work Sad

Have I used an incorrect type of capacitor? I have used 1uF, but should have used electrolytic capacitors instead? The diodes are the correct way around I think.. Sad

Please help!

The capacitors I have seem to be polarized (+ is marked on one leg..) could this be the problem?

carl0s · Nou Venit Joined: 17 Jan 2006 Posts: 7

IT'S WORKING!! I LOVE YOU VICTOR!!! IT HAS READ THE OTHER EEPROM WHICH WOULDN'T READ BEFORE, AND THIS ONE HAS READABLE INFORMATION IN IT!

carl0s · Nou Venit Joined: 17 Jan 2006 Posts: 7

It was IC1103, marked "2402", made by ST. Strangely though this was a 512byte eeprom, and was read as a 2404. The password was not decryptable but I wrote six bytes of 00 at offset 0x100 and all was well.
Wonderful dance

Oh yes, it was the capacitor polarity, and also I needed to invert some settings in the software.

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

24C02 is 256 bytes (0x00 - 0xFF), no mather the manufacturer. If you have 512 then there are 2 on the same bus and you read both of them (they have consecutive addreses). 24c02 may be more than one on the same I2C bus.
0x100 = 256, that means you wrote zeros at the begining of the other one Smile

. Better to see exactly what is the true 24c02 just for your record.

Observe A0, A1 and A2 pins (#1,#2,#3) of each eeprom. The first one has all to GND and the good one must have A0 to Vcc and A1, A2 to GND.

Well done

P.S. Did you mention this is a VAIO?

carl0s · Nou Venit Joined: 17 Jan 2006 Posts: 7

hmm that's very interesting, but I can't see any other 2402, other than the one which I read sucessfully many times with the SimpleI2C circuit. That chip has now suffered much damage around the pins and PCB and so I am frightened to try to read it any more. I need to find some kind of IC test-clip. The chip is a very small TSOP (I think) package.

Yes the machine is a VAIO TR1 sub-notebook. I will be replacing the hard drive (it uses the iPod type 1.8" drive) during the week so will take a look at the groundings with my multimeter then as it is all re-assembled now.

Thank you for your help Smile

guoheng · Nou Venit Joined: 13 Jun 2006 Posts: 7

Hi,
I am making I2C interface now. But I do not know this interface must use a 3 battery between MAX232 and 2 4.7k resistances when I connected 3 lines to eeprom?
I saw the interface pdf (author is Mr. Victor) there is 3 batteries. Thanks for your replay first.

LightenFX · Nou Venit Joined: 10 Jun 2006 Posts: 5 Location: US

I have this chip on a Dell inspiron 8100, I looked in the forum to see how to connect it, however i can't seem to understand clearly how to do it.

Questions are:

1. Mainly, how would i read it?
2. What is the pinout assigment for this chip using the Driven reader?
3. Do I have to unsolder it?

Well, thanks for your help.

LightenFX · Nou Venit Joined: 10 Jun 2006 Posts: 5 Location: US

Well, I think i would rather read the chip since i finally found it and the laptop is almost completely dismantled.

Now, what would be the procedure to read the chip? How would i connect it to the Driven reader? Those are the questions I have, I looked, but maybe in the wrong places... I would appreciate anyones help.

By the way, this has got to be one of the fastest forums, a day and i get reply, thats awesome compared to others... that is why delayed in writing back.