How to unlock CRTC registers
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How to unlock CRTC registers
I looked osdev for that info but didnt found anything about it. So, how to unlock (and lock) CRTC registers?
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Re: How to unlock CRTC registers
Bit 7 of the Vertical Retrace End Register (index 0x11) is the write protect bit. Clear that bit to remove the write protection. You can read more about it in IBM's VGA documentation and in other VGA resources linked in the wiki.
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Re: How to unlock CRTC registers
Thanks so much!Octocontrabass wrote: ↑Tue Aug 13, 2024 9:44 am Bit 7 of the Vertical Retrace End Register (index 0x11) is the write protect bit. Clear that bit to remove the write protection. You can read more about it in IBM's VGA documentation and in other VGA resources linked in the wiki.