Thread: Can OS bypass the BIOS?

  1. #1
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246

    Can OS bypass the BIOS?

    Can OS bypass the BIOS?
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  2. #2
    and the hat of int overfl Salem's Avatar
    Join Date
    Aug 2001
    Location
    The edge of the known universe
    Posts
    39,660
    If you mean run the OS without touching the BIOS, I doubt it.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

  3. #3
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    No, I mean after loading OS.
    I mean if the OS can handle all BIOS functionality in such a way that you can pick off the CMOS from mobo.
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  4. #4
    and the hat of int overfl Salem's Avatar
    Join Date
    Aug 2001
    Location
    The edge of the known universe
    Posts
    39,660
    You need the BIOS in order to load the OS.
    I don't think any of the protected mode operating systems make any reference to BIOS code once the system is up and running.
    If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.
    If at first you don't succeed, try writing your phone number on the exam paper.

  5. #5
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    In Windows, if you disable a HDD in BIOS windows wont read and detect that HDD. Why? Windows can bypass BIOS and search for connected IDE devices itself.
    Last edited by siavoshkc; 08-07-2006 at 01:40 PM.
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  6. #6
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Ireland
    Posts
    8,446
    If you disable a device through the BIOS, you are effectively instructing the system not to use that device. An operating system that wouldn't obey this would be a dangerous OS.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  7. #7
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    Quote Originally Posted by Mario F.
    If you disable a device through the BIOS, you are effectively instructing the system not to use that device. An operating system that wouldn't obey this would be a dangerous OS.
    So Fedora Core 5 is one of that dangerous OSes.
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  8. #8
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Ireland
    Posts
    8,446
    If Fedore Core 5 disregards that kind of BIOS setup, yes.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  9. #9
    User
    Join Date
    Jan 2006
    Location
    Canada
    Posts
    499
    I always thought that the operating system talked TO the BIOS, and that the BIOS did all the dirty work with the hardware....

  10. #10
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Ireland
    Posts
    8,446
    And that is my understanding as well. Besides I don't think Fedora overrides/ignore/whatever BIOS disabled devices.

    What Siav may be confused about is with how PnP deals with legacy ISA devices and the fact their IRQs set in the BIOS are overriden by windows.
    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  11. #11
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    I disabled my primary master HDD in BIOS, but Fedora detected both HDDs.

    I always thought that the operating system talked TO the BIOS, and that the BIOS did all the dirty work with the hardware....
    Me too, but it seems that it is not fully correct, as OS can do dirty works itself it doesn't need BIOS.
    Last edited by siavoshkc; 08-08-2006 at 12:41 AM.
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  12. #12
    Registered /usr
    Join Date
    Aug 2001
    Location
    Newport, South Wales, UK
    Posts
    1,273
    BIOS stands for Basic Input/Output System, so in effect it's a bit like the hardware abstraction layers that many OSes provide. You don't need a particular hard disk to work with the BIOS, as long as its interface is supported you'll be able to boot from it. The same goes for keyboards/mice, many BIOSes can convert USB HMI signals to PS/2 input, so you can use your USB keyboard with DOS with no drivers (because the BIOS "is" a driver).

    As a modern operating system's kernel provides and extends the same functionality of the BIOS, it effectively replaces it once the OS has loaded. But until the OS is there something has to tell the CPU what goes where.

    Many people these days advocate replacing the BIOS with EFI so it's more effective but it's unlikely to happen for the next year or so.

  13. #13
    Gawking at stupidity
    Join Date
    Jul 2004
    Location
    Oregon, USA
    Posts
    3,218
    Many people these days advocate replacing the BIOS with EFI so it's more effective but it's unlikely to happen for the next year or so.
    Electronic Fuel Injection hardly has a place in computers...
    If you understand what you're doing, you're not learning anything.

  14. #14
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    Electronic Fuel Injection hardly has a place in computers...
    lol

    But until the OS is there something has to tell the CPU what goes where.
    What do you mean by this? Telling CPU what?
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

  15. #15
    System Novice siavoshkc's Avatar
    Join Date
    Jan 2006
    Location
    Tehran
    Posts
    1,246
    Let me expalin what I mean:
    First BIOS does the POST.
    Second it reads the CPU registers and identifies it.
    Third looks for the boot loader and gives the control to it.
    Right?
    My question is, from now on, how much BIOS is involved. OS usees it? Or do things by itself and ignores the BIOS cmpletely? What does CMOS do now?
    Learn C++ (C++ Books, C Books, FAQ, Forum Search)
    Code painter latest version on sourceforge DOWNLOAD NOW!
    Download FSB Data Integrity Tester.
    Siavosh K C

Popular pages Recent additions subscribe to a feed

Similar Threads

  1. Detecting if OS is Windows???
    By Ktulu in forum Windows Programming
    Replies: 2
    Last Post: 11-19-2006, 02:49 AM
  2. Lost BIOS menu options?
    By PJYelton in forum Tech Board
    Replies: 3
    Last Post: 11-14-2004, 08:23 AM
  3. a simple OS
    By DavidP in forum A Brief History of Cprogramming.com
    Replies: 8
    Last Post: 06-06-2004, 10:47 PM
  4. Bios upgrade-dell latitude
    By GanglyLamb in forum Tech Board
    Replies: 4
    Last Post: 06-18-2003, 01:55 PM
  5. How do they compile code for an OS ?
    By Nutshell in forum A Brief History of Cprogramming.com
    Replies: 49
    Last Post: 03-28-2002, 12:16 AM