Due to a failed BIOS flash, the laptop does not post. The BIOS chip is a Gigadevice 25LR128DSIG.
I didn’t realize the chip was 1.8V, so the first ch341a I bought didn’t come with a 1.8V adapter which apparently didn’t work. So I bought another one with an adapter.
Now the thing is as soon as the 1.8v adapter is plugged into the second ch341a, the RUN LED shows a solid yellow and the AMS1117 chip becomes super hot.
I guess there is something wrong, but I’m not so sure what is wrong and what does this LED mean.
Now for the voltage, I found this image posted here
However, for my case, pin 8 does get 1.8V, but the rest are all 0.
Pin 8, second ch341a
Pin 6, second ch341a
Is the adapter broken?
If I plug this adapter to the first ch341a chip I got, there is no yellow RUN LED, but pin 8 only gets 1.2V and the rest are still 0.
Pin 8, first ch341a
I can actually read the BIOS of a spare ASRock N3050 with both ch341a without the adapter. ASRock didn’t label the BIOS chip, but NeoProgrammer can directly detect the chip model as W25Q64FW (which is actually 1.8V). A quick google search seems to confirm this.
I found that I had to power the laptop on to let the programmer detect the BIOS chip.
I can read, earse, and write the chip, but verification fails after the flash. The programmer reports an error like “flash check error address” at a random location. Any idea how to solve this? Should I try to desolder the chip?
You may need to… some boards acts like this due to the all circuit, like some MacBooks.
We see this more on laptop than desktop motherboards…
CMOS battery ON/OFF, PSU Stand-by ON/OFF, 3,3 or 5,0v present or not, etc…
If you didnt found any Tonfang user in this forum with same issue, that can enlighten the procedure and you have some skills on de-/soldering, you must try it…
My opinion only, you may wait for other users pov.
I refleshed again with a BIOS ROM from a different rebrand, and it actually worked. Even though I got the same error message, the laptop booted into the BIOS menu after two power cycles (maybe the first time I didn’t wait long enough).
Now the keyboard layout is different, so I have to flash the BIOS of my own rebrand back, but I can do it in Windows now.
This means the CH341A boards and adapters are surely defective…
Yep, I did see some people mentioned you have to connect to the power supply and/or battery to get it working.
I tried no power supply. No luck.
With power supply and/or battery, no luck, either.
Then suddenly the laptop booted itself, and I could finally detect the chip. I was little afraid of flashing with the laptop powered on, but I saw some people doing similar stuff, so I decided to try it.
No…these cheap USB CH341A do a general task but not specific useful on some types of ICs and/or system boards that the circuit acts like i described…and like you know have the experience on that one… thats why they are really cheap programmers.
All the best, good luck.
