Loading meh kernel above 0x10000
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ChazZeromus
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Re: Loading meh kernel above 0x10000
Oh okay. I get it. So what exactly happens if access to an address about the 20-bit limit while not having the A20 mask? I'd be afraid to hear a circuit glitch if that would happen, lol.
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Love4Boobies
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Re: Loading meh kernel above 0x10000
That's exactly what you want to happen - NOT have a mask 
The way I see it (and this is probably how all masks work) is that it is AND-ed to your address. So in this case you have a 21-bit address (say FFFF:FFFF) and your mask is ...111011111111111111111111b. You can't have addresses bigger than 21 bits anyway, and when you turn the mask off (by enabling the A20 gate), you set the 0 bit to 1 again.
The way I see it (and this is probably how all masks work) is that it is AND-ed to your address. So in this case you have a 21-bit address (say FFFF:FFFF) and your mask is ...111011111111111111111111b. You can't have addresses bigger than 21 bits anyway, and when you turn the mask off (by enabling the A20 gate), you set the 0 bit to 1 again."Computers in the future may weigh no more than 1.5 tons.", Popular Mechanics (1949)
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ChazZeromus
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