Service Forum

[Event_Horizon]

Hello. Thanks for inventing this process.

Quickly - I first made the simple circuit and couldn't get it past "EEPROM not available". I used the 3M SOIC 8 pin clamp to attach the leads. (The Pomona 5250 was flimsy crap and I got my money back).

After some trial and error I finally go the the driven circuit to work with the itester program and received the 0/0 and 1/1 simultaneously while getting the voltages that were supposed to appear in or near the ranges suggested. I ran the circuit unconnected to the P24S08 (R24RF08 clone) and (of course) got "EEPROM not available".

I attached to the password protected laptop several different ways (ground) but could NOT get this message (not available) to stop appearing. My system still boots and waits for a password but could I have damaged the SVP chip somehow ? (Some of my first circuit builds weren't properly assembled before I connected them to the system to be read.) I also tried using unsoldered needles as test leads to scl and sda while ground was on the vga socket screw hole. No change.

Is there a way to test it ? Would the system continue to ask for a password regardless of the status of the P24S08 ? Is the fact that the target system still boots a good sign ?

Thanks for any assistance you can provide.

Event.Horizon

[victor]

Mr. Event

I would get rid of the 3M thing (btw POMONA's is made for the smaller pitch, like on BIOS chips - and is not crap at all ) and I'd use two probes for SCL and SDA signals. Probes can be easily made with two sewing needles, I guess I wrote about that a few million years ago.

www.allservice.ro/forum/images/probes.jpg

Connect the GND wire to the laptop VGA connector's nuts/screws, then keep the probes on the eeprom pin5 (SDA) and pin6 (SCL) while program does its job.

If no change then the interface has issues or the COM port speed and settings are incorrect. Check in Device Manager that COM1 has 115200-8-N-1

Bit Rate: 115200
Data Bits: 8
Parity: None
Stop Bits: 1
Flow Control: None

Good luck!
_________________
Victor Voinea
ALLservice HQ, Romania.

[Event_Horizon]

Thanks for the response.

Realized that there was something flakey in my circuit. Decided to dump the hacked com cable-to-gender changer-to computer arrangement. Assuming I was going to build a pcb version I had bought female com ports and pins. I fashioned a new connector for the computer. Also found that the breadboard pops the damn Max232cpe chip and chip holder up a little bit if you bumped it. Finally got the itester to synch 1/1 and 0/0 properly.

Turned that off and ran the r24rf08 with switches...

So finally I got a dump! Hooray !

When I opened it? All zeros. Dammit.

My 3M sotc-8 worked but I've open and closed it so many times I've worn off the bottom "fangs" and it won't stay on the chip properly. I have a couple of sewing needles, a zoom lens overhead scanner, and tape so that will probably be the next thing I try...

Holding the clip on there and holding the needles carefully results in "EEPROM not available" again...

The pomona 5250 did not retain the pins in their respective shafts due to failing glue, or poorly etched grooves, or something... so the one I received was crap. If the contact points were 'teeth' they weren't staying in the jaws but dangling out like a tongue.

The bios dump gave me hope that something might actually work...

[victor]

Se that wires that go to COM port are not mirrored. Also don't use null modem cables between the port and the interface, must be a straight connection.


_________________
Victor Voinea
ALLservice HQ, Romania.

[Event_Horizon]

I ordered another 3M clip. This one stayed attached to the motherboard chip. I still get the "EEPROM not found" error. I got the thing to read *once* while using the previous clip until the bottom edge could no longer grip.

Now that I know the com port was the faulty part of my circuit (and fixed) I haven't tried to attach the original basic 2 resistor/2 diode build..yet.

I think I fried the eeprom or a nearby diode and will have to remove it and solder a replacement on there. Is there a way to test this? Or an FAQ on the removal of the chip ?


Event.Horizon

[victor]

Hi,

My bet is that the eeprom is as good as new. I've seen only one faulty I2C eeprom in all these years.

The problem is the circuit or COM port or the connections, for sure.
To cut it short: If you want my help then post some pictures here, otherwise I can't guess a solution..
_________________
Victor Voinea
ALLservice HQ, Romania.

[Event_Horizon]

I think I fried the chip *on* the R500 system to be deciphered not the MAX232ACPE chip unless the P24S08 chips are much more robust than suggested.

When I run the itester I get the 0/0 1/1 and proper voltage outputs.

It dumped to a bin file...once... with all zeros and "Eeprom not found" ever since...

Is the MAX232ACPE chip as part of the powered circuit compatible with this process ? (is it the same thing as MAX232A ?)

I left all that stuff in my lab at work so I would leave it alone for a few days... Pictures later I guess...

[victor]

1. You did not fry the P24S08 up, is just your impression
2. Of course, you could fry it if your really want. Is all a matter of will
3. Any Max232 is good.
4. Come back with the pictures.
_________________
Victor Voinea
ALLservice HQ, Romania.

[Event_Horizon]

I rebuilt the basic circuit as the problem was my com port crap interface that I corrected for the powered circuit. I moved it to this one.

Hey. I got a dumpfile ! Two actually, I ran 24rc01 and 24rf08...

I can't screencap until about 20:00 CST but here was what I got:

r24c01 - at line 0x30

00 00 00 00 00 00 00 00 ca 87 6f 7d a4 c4 1d 6c (empty space) f*f0 "

r24rf08 at line 0x330

00 00 00 00 00 00 00 00 ca 87 6f 7d a4 c4 1d 6c (empty space) f*f0 "

It's a (weird) French Canadian keyboard and I don't know if this is the literal password or one that is encrypted. I can't type the special characters * or " .

It didn't generate a visible character for "ca".

event_horizon

[victor]

Email us the dump taken with R24RF08, I guess is TCPA lock but need to be sure.
You know the email address.
_________________
Victor Voinea
ALLservice HQ, Romania.