Re: [Qemu-discuss] response to BIOS int 0x13 calls

[Dale R. Worley]

bilsch <address@hidden> writes:
> I'm a low energy QEMU user.  I use it for running a 'hobby' OS that is 
> little more than a boot sector.  It has a program that calls int 0x13 
> ah=0x48 to get the number of sectors on the hard drive.  If the call 
> returns CF=1 it means the call was unsuccessful (and presumably the # of 
> sectors info is invalid).  If I copy the 'OS' containing this BIOS call 
> to a partition on the actual hard drive and boot it, it returns CF=0 and 
> # sectors = (a reasonable number).  If I run this OS in QEMU it returns 
> CF=1 and # sectors = 0.  How do I get correct BIOS response in QEMU?

Your OS is calling the BIOS that QEMU provides for the virtual machine
that your OS is running inside of.  So the first thing to track down is
what that BIOS is and whether it actually implements INT 0x13.

Dale