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hello sir,

i am in need to read the boot sequence from bois and i have to make changes in the boot sequece into the bios by running my program( C or c++ program)

if any body know details please send to me

with luv,

chaand

Here is how to set the BIOS boot sequence:

1. When your computer is booting up, it should say somewhere "DEL to enter setup" or "F2 to edit" or something. You have to press the specified key quickly if you have a fast-booting computer!

2. Find the boot sequence on that menu, check all the sub-catagories if there are any.

3. Exit saving changes (should be another thing on the menu there)

There! now your computer will reboot and it will read off whatever you specified before it boots off the hard disk.

No mr. St8ic not that case. it is ok to enter into cmos setup and changing the boot sequence. what i need is to read the details from bios through my program and need to change it through my program ok

luv

chaand

the boot sequence must read from the bios within the dos plat form using a program and must change the boot sequence to the bios

with luv,

chaand

It depends on the type of BIOS. There is no standard. Different BIOSs have different types of booting schemes. One bios, might have only one option(old bioses), others(new) have a whole list(my has at least 4). So, what you are trying to do, is called hacking the BIOS data. You could have as well asked, how to read the supervisor password of the BIOS-it's not much harder. If you realy need to deal with this, read Ralf Brown docs.
Anton.

hai dear anton,

how i will be able to read the boot sequence information from the bios through my program.

and what is this "Ralf Brown docs" where will i get it. if any thing please send to me.

Search them in google. They are well know docs. But here is the address anyway http://www-2.cs.cmu.edu/~ralf/
As far as i remember the stuff that you are looking for is in one of the docs that contains stuff on i/o ports(about CMOS probably)

By the way, you should look for the docs named "Interrupt List".

Got into the conclution that outportb() and inportb() functions in c will help to request and read data from the cmos. but for boot sequence is still stuggling. any one have idea please reply.

Hello,

As has already been stated, there is NO STANDARD for changing the BIOS boot order from a program.

Every BIOS is different, so even if you work out how to do it on one computer, it will probably not work on a different model motherboard.

The only way is to use the BIOS menu.

Hai sir,

ok eventhough there is no standard for reading and changing the boot order from the bios.
i need a program which reads the same from the latest version of Award bios and need to change.

one idea with me is that outportb(0x70,0x2D) and inportb(0x71) awailable in C language functions. but which is analysing a single bit as boot seqeuce a,c and c,a. and it is not properly working in my system

if any idea regarding the boot sequence of A, C, And Cdrom and all with new Award bios version. please send reply.