kris@beep.UUCP (Huh?) (02/24/91)
[The walls & floor are moving! I'll never drink on this boat again!!]
Does anyone out there know anything about hacking BIOS ROMs? When
I try using the "jmp 0x0ff0000" (or whatever) to do a "warm" hardware
restart, it doesn't work. The system just seems to hang.
I suspect the problem may be in my BIOS ROM. The system is a
"Compustar XT" Fry's (I call them Cry's) Electronics house-brand,
Taiwanese if I recall correctly with 640K RAM, 2 50meg hard disks
DOS 3.2 (when it's not running UNIX 8-)). CPU speed is 4.77MHz.
CTRL-ALT-DEL works OK. The BIOS ROMs seem rather drastic; if
anyone has any advice short of getting rid of the system (its an
old friend, also $$$), I'd be glad to hear.
--
Kris
key!beep!kris -OR- woodowl!beep!kris
"For men without women
are like fish without water to swim in; Was (Not Was)
their eyes bugging out, they flop on the beach "Shadow & Jimmy"
and stare up at the girls who are just out of reach."ZECHES@FRECP12.BITNET (Nicolas Zeches) (03/02/91)
In article <177@beep.UUCP>, kris@beep.UUCP (Huh?) says: > Does anyone out there know anything about hacking BIOS ROMs? When >I try using the "jmp 0x0ff0000" (or whatever) to do a "warm" hardware >restart, it doesn't work. The system just seems to hang. > > I suspect the problem may be in my BIOS ROM. Well, i wonder if it really comes from you BIOS... First of all, the warm boot BIOS address is FFFF:0000. A simple jump to this address usually works. However, i've already had a problem withg a PS/2 that didn't accept to reboot How come ? The bios segment (40h) contains some variable that is useful for a warm boot : the word at address 40:72 (hex) should contain the value 1234h Here is an example of warm boot routine : MOV AX,0040h MOV DS,AX MOV AX,1234h MOV [0072h],AX JMP FFFF:0000 That's all folks ! I hope it will work for you... Virtually. Nicolas Zeches ZECHES@FRECP12.BITNET