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   alt.os.development      Operating system development chatter      4,255 messages   

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   Message 2,611 of 4,255   
   Joe Monk to All   
   Re: PDOS/86   
   15 Jul 21 05:39:26   
   
   From: joemonk64@gmail.com   
      
   > When PDOS/86 is running on an 80386, at startup time, it will   
   > set all 16384 selectors to map the first 512 MiB of memory,   
   > and then never ever change them.   
      
   First off, there arent 16384 selectors on an 80386.   
      
   A selector is only 13 bits wide. 2^13 = 8192.   
      
   Bits 0-1 of a selector are the privilege level, and bit 2 specifies which   
   descriptor table (GDT,LDT) you are indexing into.   
      
   https://pdos.csail.mit.edu/6.828/2005/readings/i386/c05.htm   
      
   Joe   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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