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Stop waisting everyones time

I answered no to the question "is my floppy disk or drive bad", meaning that they are both in working order.

Somehow that boot signature dw 0xAA55 is not working right. The AA is supposed to be the high byte, and is supposed to be stored LAST.
If you look at the raw data that you posted, the last two bytes are 0xAA 0x55 -- they are backwards for some reason. The problem is in your nasm code, somehow. Not in your floppy creation command.

You might try doing db 0x55, db 0xaa, to force the proper byte order. I have no idea why it might be doing this though. It's almost like your copy of nasm was compiled to be big-endian or something.

I think you should familiarize yourself with the hexdump command bewing..

You might try doing db 0x55, db 0xaa

Trying that makes qemu refuse to boot the floppy and on a physical machine, it's no different.

There is nothing wrong with the code, hexdump displays data in big endian byte order.

Brynet-Inc wrote:I think you should familiarize yourself with the hexdump command bewing..

I don't use linux except to build things that need to be built with gcc. All MY dump routines output the bytes in actual byte order, so as not to confuse people with artificial byte reorderings -- so the byte dumped at offset 0x1ff really is at offset 0x1ff! And he didn't say which dump routine he used.

bewing wrote:I don't use linux except to build things that need to be built with gcc. All MY dump routines output the bytes in actual byte order, so as not to confuse people with artificial byte reorderings -- so the byte dumped at offset 0x1ff really is at offset 0x1ff! And he didn't say which dump routine he used.

Who said anything about Linux? I sure didn't...