Service Forum

dramacydril · Interesat Joined: 09 Dec 2011 Posts: 14

Hi,

I used an old data cable and salvaged the 9pin head.

Like this one:

I soldered the simple prog together and i used the tester program, but it only shows:

0
1

(no 1 - 1)??

Here are some pictures, is everything okay?

edit (update): I made the wires a lot shorter but it still wont work. I can see my com ports in winxp system manager and set the right settings for the com ports.

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

Hello,

Do the check with itester again. Leave the wires "in the air" and take a voltmeter and see what you get:

1. Close all programs.
2. Connect the interface to COM1. Do not connect SCL&SDA wires to the locked laptop!!
3. Execute itester.exe (from the same folder) and click <Connect>

After about 10 seconds, the program will switch the "SDA/SCL out" value. "SDA in" must be IDENTICAL to it, both values must switch together having the same value after each 5 seconds. 1-1, 0-0, 1-1 and so on.
With the voltmeter, check the voltage between GND and each output wire.
They must be like:

SDA (1) = +4.1V..+5.1V; SDA (0) = -0.6V
SCL (1) = +5.1V; SCL (0) = -0.6V

If all of the above are correct then the interface and the serial port are working
_________________
Victor Voinea
ALLservice HQ, Romania.

dramacydril · Interesat Joined: 09 Dec 2011 Posts: 14

I never worked with a multimeter Sad

I have totally no idea if this is right but i checked:
I get 5.08 if the timer is on 1.
I get -0,75 when the timer is on 0

I use these:
Zenerdiode 0,5 watt (Diode type: 5,1 volt)
Resistors (2,2 k ohm)

I now get eeprom not found, i already got the 1-1, 0-0, 1-1 etc.
Com ports are okay including com settings.

I tried 100 times but still the error no eeprom detected., i think its the zeners or resistors. My setup is exactly the same like on the schematic.

What can i try now?

bob · Posted: Sun Dec 18, 2011 3:55 pm Post subject:

It's the connection to the eeprom. The eeprom is not connected, not responding, not powered

BTW, what are the COM port settigns?

dramacydril · Interesat Joined: 09 Dec 2011 Posts: 14

dramacydril · Interesat Joined: 09 Dec 2011 Posts: 14

I really dont understand why it doesnt work pff.

If i disconnect the circuit (com port) then the 24rf08 program gives me the bus error, so thats good, but still i get the eeprom error.

I just remove the x201 keyboard and mousepad cover en put the 2 needles in the correct small holes, but nothing.

Can i connect the 2 probes directly to the 24rf08 chip legs? Where is the chip located, because on the backside there are the same holes, but no chip in the area around the holes?

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

The interface looks OK, is just a matter of making contact with the eeprom.

The two alternate connection points are located under the Xprescard cage. They have a layer of paint so they won't make contact until you remove the paint. I often use a fine cutter to remove that laque then apply some small amount of soldering material over them with a fine tipped iron.

Of course, if you removed the board, then connect the two needles to the eeprom legs as per the figure below:
www.allservice.ro/forum/images/x201_eeprom.jpg

Good luck!
_________________
Victor Voinea
ALLservice HQ, Romania.