
DR
AFT
DR
AFT
DRAFT
DR
D
RAFT
DRAFT
DRA
FT DRAF
D
RAFT DRAFT DRAFT DRAFT DRAFT D
DRAFT
D
RAFT DRA
FT DRAFT DRAFT DRAFT DRA
UM10360_0
© NXP B.V. 2009. All rights reserved.
User manual
Rev. 00.06 — 5 June 2009
624 of 808
NXP Semiconductors
UM10360
Chapter 34: Appendix: Cortex-M3 User Guide
•
If
n
is 32, then the value of the result is same as the value in
Rm
, and if the carry flag
is updated, it is updated to bit[31] of
Rm
.
•
ROR
with shift length,
n
, more than 32 is the same as
ROR
with shift length
n
-32.
2.3.4.5
RRX
Rotate right with extend moves the bits of the register
Rm
to the right by one bit. And it
copies the carry flag into bit[31] of the result. See
When the instruction is
RRXS
or when RRX is used in
Operand2
with the instructions
MOVS
,
MVNS
,
ANDS
,
ORRS
,
ORNS
,
EORS
,
BICS
,
TEQ
or
TST
, the carry flag is updated to bit[0] of the register
Rm
.
2.3.5 Address alignment
An aligned access is an operation where a word-aligned address is used for a word, dual
word, or multiple word access, or where a halfword-aligned address is used for a halfword
access. Byte accesses are always aligned.
The Cortex-M3 processor supports unaligned access only for the following instructions:
•
LDR
,
LDRT
•
LDRH
,
LDRHT
•
LDRSH
,
LDRSHT
•
STR
,
STRT
•
STRH
,
STRHT
All other load and store instructions generate a usage fault exception if they perform an
unaligned access, and therefore their accesses must be address aligned. For more
information about usage faults see
Section 35–1.4 “Fault handling”
.
Fig 141. ROR#3
&DUU\
)ODJ
Fig 142. RRX
&DUU\
)ODJ