Description
Reset
Type
Name
Bit/Field
Trap on Divide by 0
This bit enables faulting or halting when the processor executes an
SDIV
or
UDIV
instruction with a divisor of 0.
Description
Value
Do not trap on divide by 0. A divide by zero returns a quotient
of 0.
0
Trap on divide by 0.
1
0
RW
DIV0
4
Trap on Unaligned Access
Description
Value
Do not trap on unaligned halfword and word accesses.
0
Trap on unaligned halfword and word accesses. An unaligned
access generates a usage fault.
1
Unaligned
LDM
,
STM
,
LDRD
, and
STRD
instructions always fault
regardless of whether
UNALIGNED
is set.
0
RW
UNALIGNED
3
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
0
RO
reserved
2
Allow Main Interrupt Trigger
Description
Value
Disables unprivileged software access to the
SWTRIG
register.
0
Enables unprivileged software access to the
SWTRIG
register
(see page 163).
1
0
RW
MAINPEND
1
Thread State Control
Description
Value
The processor can enter Thread mode only when no exception
is active.
0
The processor can enter Thread mode from any level under the
control of an EXC_RETURN value (see “Exception
Return” on page 122 for more information).
1
0
RW
BASETHR
0
June 18, 2014
176
Texas Instruments-Production Data
Cortex-M4 Peripherals