ARM Cortex-M0 - Page 37

Programmers Model
ARM DDI 0432C Copyright © 2009 ARM Limited. All rights reserved. 3-7
ID112415 Non-Confidential
See the ARMv6-M ARM for more information about the ARMv6-M Thumb instructions
Extend Unsigned byte UXTB Rd , Rm 1
Reverse Bytes in word
REV Rd , Rm 1
Bytes in both halfwords
REV16 Rd , Rm 1
Signed bottom half word
REVSH Rd , Rm 1
State change Supervisor Call
SVC #<imm>
-
e
Disable interrupts CPSID i 1
Enable interrupts
CPSIE i 1
Read special register
MRS Rd, <specreg> 4
Write special register
MSR <specreg>, Rn 4
Breakpoint
BKPT #<imm>
-
e
Hint Send event SEV 1
Wait for event
WFE
2
f
Wait for interrupt WFI
2
f
Yield
YIELD
g
1
No operation NOP 1
Barriers Instruction synchronization
ISB 4
Data memory
DMB 4
Data synchronization
DSB 4
a. Depends on multiplier implementation.
b. N is the number of elements.
c. N is the number of elements in the stack-pop list including PC and assumes load or store
does not generate a HardFault exception.
d. 3 if taken, 1 if not-taken.
e. Cycle count depends on core and debug configuration.
f. Excludes time spent waiting for an interrupt or event.
g. Executes as NOP.
Table 3-1 Cortex-M0 instruction summary (continued)
Operation Description Assembler Cycles