User manual

Glossary

Processor A processor is the circuitry in a computer system required to process data using the

computer instructions. It is an abbreviation of microprocessor. A clock source, power

supplies, and main memory are also required to create a minimum complete working

computer system.

Physical Address (PA)

The MMU performs a translation on Modified Virtual Addresses (MVA) to produce the

Physical Address (PA) which is given to AHB to perform an external access. The PA is

also stored in the data cache to avoid the necessity for address translation when data is

cast out of the cache.

See also Fast Context Switch Extension.

Read Reads are defined as memory operations that have the semantics of a load. That is, the

ARM instructions LDM, LDRD, LDC, LDR, LDRT, LDRSH, LDRH, LDRSB, LDRB,

LDRBT, LDREX, RFE, STREX, SWP, and SWPB, and the Thumb instructions LDM,

LDR, LDRSH, LDRH, LDRSB, LDRB, and POP. Java instructions that are accelerated

by hardware can cause a number of reads to occur, according to the state of the Java

stack and the implementation of the Java hardware acceleration.

RealView ICE A system for debugging embedded processor cores using a JTAG interface.

Region A partition of instruction or data memory space.

Remapping Changing the address of physical memory or devices after the application has started

executing. This is typically done to allow RAM to replace ROM when the initialization

has been completed.

Reserved A field in a control register or instruction format is reserved if the field is to be defined

by the implementation, or produces Unpredictable results if the contents of the field are

not zero. These fields are reserved for use in future extensions of the architecture or are

implementation-specific. All reserved bits not used by the implementation must be

written as 0 and read as 0.

Saved Program Status Register (SPSR)

The register that holds the CPSR of the task immediately before the exception occurred

that caused the switch to the current mode.

SBO See Should Be One.

SBZ See Should Be Zero.

SBZP See Should Be Zero or Preserved.