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Why can't I flash my 486's mobo BIOS?

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markedmundb

Senior Member
Joined
Dec 18, 2000
Location
Kent, UK
I'm trying to flash my recently purchased (for £30 w/ screen- for use as backup system/internet gateway when I get my own place & network the lot) 486 System with the latest BIOS, and awdflash keeps falling out to the dos prompt, after I type Y for reprogramming to begin.

I've reset the "reprogram BIOS" jumper to the reprogram setting.

FYI the mobo's a mitac IH4077D (R 2.07 BIOS) and the BIOS version I DL'd from the mitac support website is 2.09.

I can't remember what version of AWDFLASH is with the bios.bin file, but it's quite old, from 1994, or somesuch.

All ideas (except bin it) greatfully rcvd.
 
Probably it's stupid :)
but you must found a jumper on Mobo for reprogramming Bios, and also a setting into the Bios, like you just did.

I hope it's right.
 
Late Reply! Flashing IH4077D from Mitac Corp.

To reflash a BIOS residing on Boards that use an EFAR 80G Chipset:
(those contained usually a fixed BIOS EPROM, not an in-place-reprogrammable one so it has to replaced first).

Have two things ready:
1) AWARDFLASH Version 1.1 (only this one supports the EFAR80G Chipsets)
2) a reprogrammable Flash BIOS Chip of type 28F010 (AMD e.g.)
3) chip grip for DIL-Chips.
4) the appropriate BIOS File for the IH4077 Board you have.

Proceed:
1) be AWARE of this:
The Chip needs to be hot-flashed, so the board must be in operation while replacing the EPROM BIOS Chip against the flashable one! Because its contents are residing in the RAM and are running from there (BIOS Shadow RAM must be enabled!), the ROM Chip is disabled already and can be generally replaced while the Board is powered on. Else you have to reprogram the Flash BIOS using an external programmer, what is an option of course.
Remove all additional Cards except the video card to leave on the ISA Slot.
The BIOS should be set to SAFE Settings (Defaults loaded, TURBO mode set to OFF so it goes slower and safer for this delicate procedure!).

2) Loosen the BIOS Chip first so you can easily pull it out later, but must be still able to boot up.
3) Power ON the board, loading a plain DOS from a Diskette with no drivers present, but it has to contain the flashing tool and the BIOS file.
4) Hit pause NOW. -> OS is halting.
5) Carefully REMOVE the EPROM Chip from its socket. note where the notch was directed to.
6) Carefully INSERT the Flash Chip 28F010 onto the socket (notch-over-notch direction, must fully cover the socket now, no pins must be bend or outside! else damage occurs instantly!).
7) First, hit any key, now load the AWARDFlash 1.1 utility, use the bios file and start programming the chip.
8) if that was successful (no Verify errors, successful message displayed), the bios chip is now written properly.
9) Exit the tool and reboot the Board.
10) Clear CMOS once now, then Load setup defaults again.

:fight: Disclaimer: "Hot-Flashing is an out-of-order procedure and therefore considered to be NOT safe from a technical standpoint!":
No warranties given. No responsability taken for this procedure to be safe, no responsability for damages occurring doing so. The PC User itself is at full risk undergoing this procedure on his machine/s ! Use an electrostatic strip for replacing the Chips!
(it is not safe to 100% but it should work under normal conditions).
 
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