There was a problem returning from long mode to real mode

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ccya
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There was a problem returning from long mode to real mode

Post by ccya »

I'm not currently writing any drivers in 64-bit long mode, so I'm going to use the BIOS as a driver, but I'm experiencing a triple glitch and return address error when returning 16-bit real mode from 64-bit long mode

Code I referencedviewtopic.php?f=1&t=23125


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Last edited by ccya on Thu Jul 27, 2023 5:58 pm, edited 2 times in total.
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Octocontrabass
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Re: There was a problem returning from long mode to real mod

Post by Octocontrabass »

ccya wrote:I'm going to use the BIOS as a driver
This does not work with UEFI.
ccya wrote:I'm experiencing a triple glitch and return address error when returning 16-bit real mode from 64-bit long mode
Where? Which exception? Are you using a virtual machine?
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ccya
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Re: There was a problem returning from long mode to real mode

Post by ccya »

refer to the ReactOS code to solve this problem，return to real mode from long mode
https://github.com/reactos/reactos/blob ... 64/entry.S
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rdos
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Re: There was a problem returning from long mode to real mode

Post by rdos »

Returning to real mode is not the problem. The problem is that there might be no real mode BIOS that you can use.
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