Announcement

Collapse
No announcement yet.

CH134A Programmer - Can't write to BIOS chip

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    CH134A Programmer - Can't write to BIOS chip

    Hi all, unfortunately I haven't been able to find a solution on this for myself. I'm no expert in programming these ICs, so I'm hoping I've missed something embarrassingly obvious!

    After screwing up a BIOS setting on an old laptop rendering it unrecoverable I bought a cheap CH134A programmer & test clip. I'm sure everyone knows the ubiquitous sub $5 listing on their favorite import site.

    The chip I am trying to write is an Eon EN25F32

    I can dump the BIOS fine as far as I know, but I can't seem to erase or write to the chip. AS Programmer in windows won't erase and gives an error: refer to datasheet or try unprotect. The unprotect attempt just hangs and returns all the SREG options as FFFFFFF

    Flashrom in verbose mode hangs on

    Found Eon flash chip "EN25F32" (4096 kB, SPI).
    Reading old flash chip contents... done.
    Erasing and writing flash chip... Trying erase function 0... 0x000000-0x000fff:E
    I looked through the datasheet but I don't know enough about flash ROM's to actually make good use of the info. I have included it for quick reference if it's helpful.

    I have heard some say the supplied cheap cable is no good, but then others say that it's fine for just fixing BIOS' you broke. Thoughts on replacing the test clip cable? I think it is fine as it reads reliably.
    Attached Files

    #2
    Re: CH134A Programmer - Can't write to BIOS chip

    Remove it from the board and try again. There are usually components interfering with it when you read it on the board.

    Comment


      #3
      Re: CH134A Programmer - Can't write to BIOS chip

      Originally posted by diif View Post
      Remove it from the board and try again. There are usually components interfering with it when you read it on the board.
      That worked a treat and makes a lot of sense really. That being said, I am surprised that I've never seen that mentioned elsewhere, at least not that I can see. There's a lot of videos of people doing similar BIOS recovery onboard

      Off board recovery went well and the machine is now fixed and working again, thanks for the suggestion.

      Comment


        #4
        Re: CH134A Programmer - Can't write to BIOS chip

        Glad you got it fixed.
        I've seen it mentioned a few times, usually whenever there are issues reading on the board as it's always worked before.

        Comment

        Working...
        X