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13.2 Two ways to Execute 80286 Tasks

When porting 80286 programs to the 80386, there are two cases to consider:
  1. Porting an entire 80286 system to the 80386, complete with 80286 operating system, loader, and system builder.

    In this case, all tasks will have 80286 TSSs. The 80386 is being used as a faster 286.

  2. Porting selected 80286 applications to run in an 80386 environment with an 80386 operating system, loader, and system builder.

    In this case, the TSSs used to represent 80286 tasks should be changed to 80386 TSSs. It is theoretically possible to mix 80286 and 80386 TSSs, but the benefits are slight and the problems are great. It is recommended that all tasks in a 80386 software system have 80386 TSSs. It is not necessary to change the 80286 object modules themselves; TSSs are usually constructed by the operating system, by the loader , or by the system builder . Refer to Chapter 16 for further discussion of the interface between 16-bit and 32-bit code.


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