OSDev.org

Posted: **Fri Aug 30, 2002 6:23 am**

Why doesn't this:

asm("mob %dl,%dl":"=d" (drive));

work?
I get this error:

Code: Select all

parse error before ":"

also, when you boot a partition, how does it know what the second sector is? (the bootblock)

Posted: **Fri Aug 30, 2002 6:44 am**

humm ... mob is not a valid opcode, i guess this is a typo of mov ...

anyway, mov dl, dl is not valid either. If what you want to do is storing the dl value in drive, try

Code: Select all

char drive;
asm ("movb %1,%dl":"=g"(drive));

optionnally,

Code: Select all

asm ("":"=d"(drive));

might work as well ...

Posted: **Fri Aug 30, 2002 7:19 am**

tnx it works

just checked the minix source, and I saw it reads the mbr to check in what sector it is...
but I can't find it in the linux source (reading mbr, 0.0.1)
also, when I put my ide cable on the other port linux doesn't boot... so I don't think it reads the mbr... perhaps it stores the stuff in the bootsector....

Posted: **Fri Aug 30, 2002 7:47 am**

frank wrote: tnx it works

just checked the minix source, and I saw it reads the mbr to check in what sector it is...
but I can't find it in the linux source (reading mbr, 0.0.1)
also, when I put my ide cable on the other port linux doesn't boot... so I don't think it reads the mbr... perhaps it stores the stuff in the bootsector....

uh ??? usually, only disk #1 is bootable by the BIOS. If you want to boot another disk than /dev/hda, you should normally put a multi-boot software on the Master Boot Record of drive /dev/hda which will load the kernel on another (defined in MBR or asked to the user) disk.

OSDev.org

ay&t

ay&t

Re:ay&t

Re:ay&t

Re:ay&t