Problems with BIOS Int 0x13 (ext) and high memory in QEMU.

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Roman
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Problems with BIOS Int 0x13 (ext) and high memory in QEMU.

Post by Roman »

Hello. I've encountered a strange problem with my boot loader in QEMU, it perfectly loads sectors to any low memory location, but fails with 0xFFFF:0x10. Sectors get written to 0x0000 (i.e. BIOS IDT is overwritten). I have A20 and unreal mode enabled. The code works successfully with any addresses in VMWare. Did anyone encounter any similar problem?
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Octocontrabass
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Re: Problems with BIOS Int 0x13 (ext) and high memory in QEM

Post by Octocontrabass »

Those functions only support loading data to the first 640kB when using segment:offset addresses.

See this post for some alternatives you can try.
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Roman
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Re: Problems with BIOS Int 0x13 (ext) and high memory in QEM

Post by Roman »

Octocontrabass wrote:Those functions only support loading data to the first 640kB when using segment:offset addresses.

See this post for some alternatives you can try.
Thank you.
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