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Motorola DSP96002 User Manual

Page 790

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8

MOTOROLA

will load the least recently used cache sector tag with the 25 most significant bits of the
sum and then lock that cache sector. The instruction will update the LRU stack according-
ly.

The displacement is a 2’s complement 32-bit integer that represents the relative distance
from the current PC to the address to be locked. Short Displacement, Long Displacement
and Address Register PC Relative addressing modes may be used. The Short Displace-
ment 15-bit data is sign extended to form the 32-bit PC Relative Displacement.

The PLOCKR instruction is enabled only in cache mode. In PRAM mode it will cause an
illegal instruction trap to occur.

2.5.4

PUNLOCKR label or PUNLOCKR Rn

The PUNLOCKR instruction unlocks the cache sector to which the sum (PC + specified
displacement) belongs. If the sum does not belong to any cache sector, and is therefore
definitely unlocked, nevertheless, the instruction will load the least recently used cache
sector tag with the 25 most significant bits of the sum. The instruction will then update the
LRU stack accordingly.

The displacement is a 2’s complement 32-bit integer that represents the relative distance
from the current PC to the address to be locked. Short Displacement, Long Displacement
and Address Register PC Relative addressing modes may be used. The Short Displace-
ment 15-bit data is sign extended to form the 32-bit PC Relative Displacement.

The PUNLOCKR instruction is enabled only in cache mode. In PRAM mode it will cause
an illegal instruction trap to occur.

2.5.5

PFREE

The PFREE instruction unlocks all the locked cache sectors.

The PFREE instruction is enabled in both the cache mode and the PRAM mode.

2.5.6

PFLUSH

The PFLUSH instruction will flush the whole cache, unlock all cache sectors, set the LRU
stack, and tag registers to their default values.

The PFLUSH instruction is enabled both in cache mode and PRAM mode.