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.
8-50