Motorola PowerQUICC II MPC8280 Series Reference Manual page 1433

Throughput. The measure of the number of instructions that are processed
U
UISA (user instruction set architecture). The level of the architecture to
User mode. The unprivileged operating state of a processor used typically by
V
VEA (virtual environment architecture). The level of the architecture that
Virtual address. An intermediate address used in the translation of an
Virtual memory. The address space created using the memory management
W
Watchpoint. An event that is reported, but does not change the timing of the
Word. A 32-bit data element. Note that on other processors a word may be a
Write-back. A cache memory update policy in which processor write cycles
Write-through. A cache memory update policy in which all processor write
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per clock cycle.
which user-level software should conform. The UISA defines the
base user-level instruction set, user-level registers, data types,
floating-point memory conventions and exception models as seen by
user programs, and the memory and programming models.
application software. In user mode, software can only access certain
control registers and can access only user memory space. No
privileged operations can be performed. Also referred to as 'problem
state'
describes the memory model for an environment in which multiple
devices can access memory, defines aspects of the cache model,
defines cache control instructions, and defines the time-base facility
from a user-level perspective. Implementations that conform to the
PowerPC VEA also adhere to the UISA, but may not necessarily
adhere to the OEA.
effective address to a physical address.
facilities of the processor. Program access to virtual memory is
possible only when it coincides with physical memory.
machine.
different size.
are directly written only to the cache. External memory is updated
only indirectly, for example, when a modified cache block is cast out
to make room for newer data.
cycles are written to both the cache and memory.
Glossary of Terms and Abbreviations
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