Table of Contents
Advertisement
instruction is issued to a damaged CPU timer or (2) a SET CLOCK
COMPARATOR or STORE CLOCK COMPARATOR is issued to a damaged
clock comparator.
•
Recovery Report. This interruption can occur when PSW bit 13 and the
recovery report mask bit are on.
It
indicates the instruction retry facility was
successful in correcting a retryable malfunction that occurred during the
execution of an instruction, a double-bit error in processor storage was
corrected, or channel data buffer or high-speed buffer reconfiguration was
done without loss of data.
•
External Damage. This interruption can occur when PSW bit 13 and the
external damage mask bit are on.
It
is implemented only for System/370
mode. The ED bit is stored in the machine check code, and the external
damage code at location 244 indicates the reason for the interruption.
External damage bits 2, 3, and 4 are implemented in 4381 Processors to
indicate
(1)
a processor storage error or protect key error was not corrected
during an
I/0
operation, (2) one or more channels have detected an error of
such severity that operations cannot continue and each has entered the
not-operational state while signaling system reset to their attached devices
(channel-not-operational condition), or (3) one or more channels have lost
power or detected an error of such severity that operations cannot continue
and all these channels may not have signaled system reset to their attached
devices (channel control failure condition).
Degradation. This interruption can occur when PSW bit 13 and the external
damage mask bit are on. Degradation is set when a portion of the high-speed
buffer is deleted (malfunctioning bit is turned on in a directory entry).
•
Pending Channel Report. This interruption can occur during System/370-XA
mode of operation if PSW bit 13 and the channel status mask bits are on to
indicate one or more channel report words are pending. Channel report words
provide information related to a channel subsystem recovery or the completion
of a RESET CHANNEL PATH instruction.
•
Channel Subsystem Damage. This interruption can occur during
System/370-XA mode of operation when PSW bit 13 is on.
It
indicates a
multiple-bit or uncorrectable double-bit error occurred in channel or
subchannel data located in auxiliary storage.
104
A Guide to the IBM 4381 Processor
Advertisement
Table of Contents
