Service Forum

[FrozenAngel]

I cant get passed the power on password on a 770x and a 600 removed the cmos batterys and main batterys and power for 24 hours still no luck any ideas f1 key does not go anywere but to the password prompt no f1 and or f12 prompt in bottom corner of machine either of them

pressing the f1 key apon boot brings up the password prompt and when programer is used get eprom not available

about ready to give up must be doing somthing wrong my driven programer would register bus or circuit not there till i added the battery pack then it worked to get the eprom not availabe error

[victor]

Forget the F1 key, not all models use F1 to enter BIOS. Just wait until pwd prompt.

driven-i2c is the one you need for that model, and of course it must be powered by the 3 AA batteries. For driven cir cuit you have to use:

[FrozenAngel]

ok i used the circuit as you stated but i get no circuit or bus error here is pictures of my circuit as can see i copied http://www.rkawakami.net/ibm_600x/bios_pass/index.html#Alternate programer to the T even down to the 1uF resistors whats wrong with circiut ?please http://i192.photobucket.com/albums/z229/FrozenAngel01/1.jpg and http://i192.photobucket.com/albums/z229/FrozenAngel01/2.jpg

just a note the yellow wire running over the max232 is my power wire for the 3 AA batterys and switch
and the orange and yellows outside center are just to join the outer bars there are a break in this bread board there

[victor]

NTE7142..I got to search for its datasheet to see this is a MAX232 clone and it needs 100nF caps.
However, the ones you have set in there looks to me like 1pF, of course there are many eratic notations, for example the line under could be a x10 or whatever, definitely those ones can't be 100nF (0.1uF).

Change the caps.
_________________
Victor Voinea
ALLservice HQ, Romania.

[papaseed]

Hi, I used the NTE7142 with 1uf capacitor (ML) with no problem. There were times when MAX232 having 'eeprom not found' but NTE7142 was able to read.

[victor]

The caps in the pictures are not 1uF but 1pF (pico) -1nF (nano), upon that notation and size, my guess is that they are 1nF.

1uF instead of 0.1uF is ok, but those are not 1uF! Better to take a capacimeter and check them or even better buy 100nF mylar caps

MAX232 or NTE or whatever, that is not importat as long as the circuit is built by the book..
_________________
Victor Voinea
ALLservice HQ, Romania.

[FrozenAngel]

Ok changed the capasitors and success sorta, I guess ,I got a read from eprom but think its wrong here is pictures of my eprom in ibmpass there really small and only thing i can see might be password is susan with the aa switch on but it doesnt work
and

[victor]

The SVP is "SUSAN" for sure, maybe you have the HD password set as well. Remove the drive, type the SVP and that's it

Good job
_________________
Victor Voinea
ALLservice HQ, Romania.

[FrozenAngel]

ok removed hard drive and tryied it still not working . did I have to run the patcher after I read the eprom ?

[victor]

The SVP is "susan" or "susqn" for french keyboards, that is it.
_________________
Victor Voinea
ALLservice HQ, Romania.

[FrozenAngel]

discoverd the problem here i sat racking my brain trying to figure out why the password wasnt working even found a post of if dont work first time try another somthing or other well thought what the heck i will try the susqn and hiting the q i noticed it wasnt working well proceeded to watch this time when i typed in suzan found the z and a were not working either the keyboard is fine its the pc board the keyboard hooks into is shot oh well at least I cracked the password

thanks for your help and patents vic

ps still working on the 770x that ones giving me grief of eprom not ready will try and resolder the wires again if that dont work i am thinking of breaking down and taking it appart and unsoldering chip and do it that way (easy access to the eprom if i have the right one by the memory )