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10.2 Software Initialization for Real-Address Mode

In real-address mode a few structures must be initialized before a program can take advantage of all the features available in this mode.

10.2.1 Stack

No instructions that use the stack can be used until the stack-segment register (SS) has been loaded. SS must point to an area in RAM.

10.2.2 Interrupt Table

The initial state of the 80386 leaves interrupts disabled; however, the processor will still attempt to access the interrupt table if an exception or nonmaskable interrupt (NMI) occurs. Initialization software should take one of the following actions: