Note
(Cont'd)
Privileged
Instructions
Bits
12
through 14
are
the
direct
state
initiation bits. The three-bit
direct
state
initiation codes
that
may be specified
are
as follows:
000 -
Go
to Machine Condition
State
P
4.
001 -
Go
to
Interrupt
Control
State
P
3.
010 -
Go
to
Interrupt
Response
State
P
2
•
011-
Go
to
Processing
State
Pl.
Programming Note: The leftmost
bit
of
the
three-bit direct
state
initiation field
must
be zero. (This is a programming restriction.)
Bit
15 is the indirect control flag bit.
If
indirect
state
control is specified
(bit
15 =
1),
the
three-bit direct
state
initiation field is ignored. The three-
bit
interrupted
state
identifier
(lSI),
which indicates
the
last
state
inter-
rupted, specifies the
state
to be initiated. This information is contained in
the
Interrupt
Status
register
of
the
state
being terminated.
If
bit
15 =
0,
direct
state
initiation is used.
105
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