Bootloader: Reading sectors to address 0xFE00

[kraks]

Hi,

I just can't get my bootloader to load to address 0xFE00 with interrupt 0x13, ah=2. It works with any address below and also 0x10000. My tries were:

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es=0x0000, bx=0xFE00
es=0x0FE0, bx=0x0000
es=0x0F00, bx=0x0E00

Bochs tells me in bochsout.txt:

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Booting from 0000:7c00
prefetch: EIP [00010000] > CS.limit [0000ffff]
WARNING: HLT instruction with IF=0!

I really have no clue why this fails, it never returns from the interrupt. Does someone know the problem or could look through the source-code? I cut it down to a minimal example, see here.

Thank you in advance,
kraks

[sebihepp]

You didn't initialize the Stack. The Stack grows downwards. Therefore your have to set
the stackpointer (sp) to a value greater than 0. And make sure you don't overwrite anything
like the BIOS.

Sebihepp

[kraks]

Gnarg, what a dumb error! Thank you so much!