From: nowhere@nevernet.at   
      
   On 01/09/2022 14:48, muta...@gmail.com wrote:   
      
   [...]   
      
   > No, default status is no wraparound, but some   
   > environments may wrap around anyway due to the fact   
   > that there are 20 or fewer address lines.   
      
   The KEY to wrap around at 1MB once was the A20 gate,   
   it's now just an historical thing found only in museums.   
   PCs don't even have an A20 gate anymore (==always ON).   
      
   the HMA (0010_0000 aka FFFF:0010..) was very often used   
   by DOS and friends, so they needed A20 ON.   
      
   easy to make it wrap at 1MB with segment limits.   
   but it will wrap only if the access is aligned while   
   crossing the boundary with a multi-byte instruction   
   end up in a Seg-Fault or with an GP-error if PM.   
   __   
   wolfgang   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)