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Chapter 12 Instruction Cache
3.Operating mode conditions
3. Operating mode conditions

Cache status in various operating modes

The table below indicates the prevailing state for disable and flush when the associated bit is
changed by bit manipulation instruction, etc.
Immediately
after a Reset Disable (FNAB=0) Flushed
Cache Memory Contents
undefined The preceding state is held.
Rewritingis impossible while
the cache is disabled.
The preceding state is held.
Tag Address
Tag Contents
undefined The preceding state is held.
Rewriting is impossible while
the cache is disabled.
The preceding state is held.
Sub-block
Valid Bit Contents
undefined The preceding state is held.
Rewritingis impossible while
the cache is disabled.
The preceding state is held.
LRU Bit Contents
undefined The preceding state is held.
Rewritingis impossible while
the cache is disabled.
The preceding state is held.
Entry Lock
Bit Contents
undefined The preceding state is held.
Rewritingis impossible while
the cache is disabled.
The preceding state is held.
(entry lock release is required)
TAG Valid
Bit Contents
undefined The preceding state is held.
Flushingispossible while the
cache is disabled.
All entries are invalid.
RAM Normal Mode The precedingstate is held.
Flushing is possible while
the cache is disabled.
The preceding state is held.
Control
Register Global
Lock Unlock The preceding state is held.
Rewriting is possible while
the cache is disabled.
The preceding state is held.
Auto lock
Fail No fail Thepreceding state is held.
Rewriting is possible while
the cache is disabled.
The preceding state is held.
Entry Auto
Lock Unlock The preceding state is held.
Rewriting is possible while
the cache is disabled.
The preceding state is held.
Entry Lock
Release No release The preceding state is held.
Rewriting is possible while
the cache is disabled.
The preceding state is held.
Enable Disable Disabled The preceding state is held.
Flush Not flushed Thepreceding state is held.
Rewriting is possible while
the cache is disabled.
Flushed in cycle following
memory accessing.
Reverts to 0 subsequently.