User's Manual

THE 80286 INSTRUCTION SET
Index must be within GOT limits else #GP (TSS selector)
AR byte must specify available TSS (bottom bits 00001) else #GP (TSS selector)
Task State Segment must be PRESENT else #NP (TSS selector)
SWITCH3ASKS with nesting to TSS
If interrupt was caused by fault with error code then
Stack
limits must allow push of two more bytes else #SS(O)
Push error code onto stack
IP must be in CS limit else #GP(O)
NOTE
EXT
is 1 if an external event (Le., a single step, an external interrupt, an MF exception, or
an MP exception) caused the interrupt;
0 if not (Le., an INT instruction or other exceptions).
PROTECTED MODE EXCEPTIONS
#GP, #NP, #SS, and #TS, as indicated in the list above.
REAL ADDRESS MODE EXCEPTIONS
None; the 80286 will shut down if the SP = 1, 3, or 5 before executing the INT or INTO instruction-
due to lack of stack space.
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