Unfortunately I don't have any soldering tools or experience, so if you could give an advice about ISP programming (In-System-Programming/In-Situ-Programming) , it will be super helpful!
I teardown a bricked laptop, removed AC power, laptop's power battery, and even a small CMOS battery, and now I am trying to write a working BIOS image to laptop's SPI flash chip using a SOIC8 test clip.
But here is a problem: I could read a dump from this BIOS chip without problems, however it fails when I am trying to write - so the contents of BIOS flash chip are remaining unchanged. Luckily I found out this helpful wiki page - http://flashrom.org/ISP , which describes common problems with this ISP method of flashing, as well as gives 3 hints for solution! Sadly this page is currently down, so here is a screenshot: http://i.imgur.com/SJEYHR2.png
1. - tried to make shorter wires, less than 10cm as they recommend - it did not help 2. - soldering is out of possibility, cant do it, and also: wires are already short and they are good quality (pure copper) 3. - This hint looks more promising, but I need help in understanding this piece of information: "disconnect Vcc from the programmer and power it with its normal PSU"
If I understand correctly, by Vcc they mean Vcc pin of the BIOS flash chip. But if I disconnect Vcc from the programmer, what is "normal PSU" which should power this Vcc pin?
Should I connect to motherboard a laptop's power battery, or small CMOS battery, or AC adapter of laptop, so that this Vcc pin would be powered by them, or it is forbidden to do it while using SPI programmer in the same time? Or its better to try to power Vcc of flash chip from "USB to TTL" adapter - which has this 3V3 (3.3V) voltage pin?
Yours faithfully, Robert Brown
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r_brown100r＠aim.com