Recently I have brought a original UNO for modifying and flashing various types of bios. I had a dedicated one click bios programmer which was very expensive but few days ago it failed. So I thought it is a good opportunity to learn how bios works in details. After searching on google, I saw people doing everything with bios via Arduino. So I bought one. But now I cant get my head around this as I couldn't find what I am looking for. My first goal is to extract bios from the flash chip and re-program the flash with another bios.
The current bios flash I have, is a Winbond 25Q80DVDAIG. Upon searching for data-sheet, I found this data-sheet. My bios flash is in 8pin 300 mil PDIP package.
For this bios flash I have followed this guide. I have wired every thing following the schematic provided in the guide. I have bought the resistors from a local store. After measuring their values, 10K is 9.64K, 100ohm is 94 to 99ohm, 220ohm is 210 to 220ohm. So they are not so accurate. But still I proceed and connected my UNO to pc. in the Arduino software I run some tests to see if everything is working or not. But when I print manufacturer_id, device_id in serial monitor, I get 0, 0. But according to the datasheet, manufacturer_id should be EFh and device_id should be 13h.
Now I don't know if the bios is dead or the UNO board can't communicate with the bios. Is there any way to just test the bios without this schematic if it is ok or dead? like with multimeter?
Another thing, On the guide there is a instruction, "First, make download_rom() function only active and flash the sketch into your Arduino.". What does it mean? How can I make download_rom() function active or only active? What does even only active means?
If you know any other easy to use guide for this bios flash, please let me know. Also, I have seen EEProm lib in Arduino software. Will it work on this bios flash?
Thanks in advance for the help. Very much needed. Appreciate it.