Atmel SAM4S Xplained Pro Starter Kit Atmel ATSAM4S-XSTK ATSAM4S-XSTK Hoja De Datos
Los códigos de productos
ATSAM4S-XSTK
103
SAM4S [DATASHEET]
11100E–ATARM–24-Jul-13
CMPEQ R0, #0 ; Did this succeed?
BNE try ; No – try again
.... ; Yes – we have the lock
12.6.4.9 CLREX
Clear Exclusive.
Syntax
CLREX{cond}
where:
cond
Operation
Use CLREX to make the next STREX, STREXB, or STREXH instruction write 1 to its destination register and fail to
perform the store. It is useful in exception handler code to force the failure of the store exclusive if the exception occurs
between a load exclusive instruction and the matching store exclusive instruction in a synchronization operation.
perform the store. It is useful in exception handler code to force the failure of the store exclusive if the exception occurs
between a load exclusive instruction and the matching store exclusive instruction in a synchronization operation.
See
for more information.
Condition Flags
These instructions do not change the flags.
Examples
CLREX