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Program Exceptions:
Privileged Operation
Programming Note
The instruction may be used to test the page
address and state of a page and return its frame
index, if any, without raising an access exception.
LOAD PSW
o
8
16
20
31
The current PSW is replaced by the contents of the
doubleword at the location designated by the
second-operand address.
If
the new PSW specifies the BC mode,
information in bit positions 16-33 of the new PSW
is not retained as the PSW is loaded. When the
PSW is subsequently stored, these bit positions
contain the new interruption code and the
instruction-length code.
A serialization function is performed.
The operand must be designated on a
double word boundary; otherwise, a specification
exception is recognized, and the operation is
suppressed. The operation is suppressed on
addressing and protection exceptions.
The value which is to be loaded by the
instruction is not checked for validity before it is
loaded. However, immediately after loading, a
specification exception is recognized and a program
interruption occurs when the newly loaded PSW
specifies the EC mode and the contents of bit
positions 0, 2-5, 16,:, 17, and 24-29 are not all
zeros. In these cases, the operation is completed,
and the resulting instruction-length code is zero.
Bits 8-15 of the instruction are ignored.
Condition Code: The code is set as specified in the
new PSW loaded.
Program Exceptions:
Access (fetch, operand 2)
Privileged Operation
Specification
MAKE ADDRESSABLE
'B210'
o
16
20
31
If
connected, the storage page designated by the
second-operand address enters the addressable
state. If already addressable, the page remains in
the addressable state.
Bits 8-20 of the second-operand address
designate the page. Bits 0-7 and 21-31 of the
address are ignored.
If the page is in the disconnected state, a
page-transition exception is recognized, and the
operation is suppressed.
The condition code indicates whether the page
was addressable
(1)
or connected (0) before.
Resulting Condition Code:
o
Page was connected
1
Page was already addressable
2
3
Program Exceptions:
Addressing (operand 2)
Page Transition
Privileged Operation
MAKE UNADDRESSABLE
'B21E'
o
16
20
31
If addressable, the storage page designated by the
second-operand address enters the connected state.
If
already connected, the page remains in the
connected state.
Bits 8-20 of the second-operand address
deSignate the page. Bits 0-7 and 21-31 of the
address are ignored.
If
bits 8-20 of the second-operand address are
zeros, that is, page 0 is specified, a specification
exception is recognized, and the operation is
suppressed.
If the page is in the disconnected state, a
page-transition exception is recognized, and the
operation is suppressed.
Chapter 10. Control Instructions
10-7
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