360 Assembly/360 Instructions/ISK

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ISK - Insert Storage Key - Opcode 09 - RR Instruction (360 Only) Privileged Instruction

Format[edit]

Opcode[edit]

RR Instruction (2 bytes)
Byte 1
bits (0-7)
Byte 2
target register
(8-11)
source register
(12-15)
(in hex) Opcode
09
(4 bits)
0..F / (dec 0..15)
(4 bits)
0..F / (dec 0..15)
  • The first argument is a target register which value is affected by the instruction.
  • The second argument is the source register.
  • The target register and source register values are 0 to 15.

Example usage[edit]

ISK R1,R2

Availability[edit]

The ISK instruction is available only on 360 models. It is a privileged instruction.

Purpose of Instruction[edit]

This instruction is used to get the Storage Key for the address specified in the Second operand and store into the first operand's bottom byte(1byte). ISK instruction provides support to get the storage key in 2K units of Page. ISKE will get the storage key for the 4K units of page.

Typical Usage[edit]

Operation[edit]

This is a privileged instruction, and is only available on the 360 series. The ISKE instruction is available on later 370 and zSystem processors.

Condition Codes[edit]

Condition codes are not changed.

Exceptions and Faults[edit]

  • Privileged Operation
  • Invalid Opcode (370 and z/System)
Previous Instruction
IPTE
360 Assembly Instructions   Next Instruction
ISKE
Previous Opcode
08
Next Opcode
0A