OP = 95
AF is the processor selection field. May be specified as an indirect field length. A literal flag will cause an Invalid Instruction (IEX = 21) fault.
BF is the variant and may be specified as an indirect field length. The following variants may be specified:
|00||Read Time of Day Timer|
|01||Read and Clear Processor Timers|
A is the address of the memory location where the timer information is to be stored. Address may be indexed, indirect or extended. The final address controller must equal UN or cause an Invalid Instruction (IEX = 03) fault.
The Read Timer instruction is used to retrieve the current Time-Of-Day timer or the processor timers from the specified processor.
The Read Time of Day Timer instruction will store the twenty digit Time of Day Timer at the memory location specified by the A address.
The Read and Clear processor timers instruction will store the following accumulated processor times for the processor specified by the AF field at the memory location specified by the A address. Then the processor timers are reset to zero. The resolution of the processor timers is in microseconds. See Compatibility Notes A.36.
|IDLE Mode Time||00 - 11|
|KERNEL Mode Time||12 - 23|
|INTERRUPTING Mode Time||24 - 35|
This variant of the Read Timer instruction may only be executed with Privileged Enable set, or an Invalid Instruction (IEX = 02) fault is reported.
Note that these accumulated processor times are update by a processor upon entry into and/or exit from KERNEL Mode. As a result, the accumulated times for a processor not currently in KERNEL mode are only up-to-date as of the last time that processor was in KERNEL mode. In order to get completely up-to-date processor times it is therefore recommended that this instruction only be executed for a processor while that processor is in KERNEL mode.
The Overflow Flag is set if the processor number specified in AF is greater than the number of allowable processors (BF=01). Otherwise the overflow flag is reset.
The Comparison Flags are not affected by this instruction.
Field overlap is not applicable to this instruction.
|95||00||00||A Field UN|
BEFORE AFTER A FIELD nnnnnnnnnnnnnnnnnnnn 20170627001234567890 COMPARISON nn unchanged OVERFLOW nn 0