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SAM4CP [DATASHEET]
43051E–ATPL–08/14
Conditional execution
If the condition code flags indicate that the corresponding condition is true when the instruction starts
executing, it executes normally. Otherwise, the instruction does nothing.
Context
The environment that each process operates in for a multitasking operating system. In ARM
processors, this is limited to mean the physical address range that it can access in memory and the
associated memory access permissions.
Coprocessor
A processor that supplements the main processor. Cortex-M4 does not support any coprocessors.
Debugger
A debugging system that includes a program, used to detect, locate, and correct software faults,
together with custom hardware that supports software debugging.
Direct Memory Access
(DMA)
An operation that accesses main memory directly, without the processor performing any accesses to
the data concerned.
Doubleword
A 64-bit data item. The contents are taken as being an unsigned integer unless otherwise stated.
Doubleword-aligned
A data item having a memory address that is divisible by eight.
Endianness
Byte ordering. The scheme that determines the order that successive bytes of a data word are stored
in memory. An aspect of the system’s memory mapping.
See also
“Little-endian (LE)”
and
“Big-endian (BE)”
.
Exception
An event that interrupts program execution. When an exception occurs, the processor suspends the
normal program flow and starts execution at the address indicated by the corresponding exception
vector. The indicated address contains the first instruction of the handler for the exception.
An exception can be an interrupt request, a fault, or a software-generated system exception. Faults
include attempting an invalid memory access, attempting to execute an instruction in an invalid
processor state, and attempting to execute an undefined instruction.
Exception service routine
See
“Interrupt handler”
.
Exception vector
See
“Interrupt vector”
.
Flat address mapping
A system of organizing memory in which each physical address in the memory space is the same as
the corresponding virtual address.
Halfword
A 16-bit data item.
Illegal instruction
An instruction that is architecturally Undefined.