Set the endianness bit in the CPSR, without affecting any other bits in the CPSR.
SETEND cannot be conditional, and is not permitted
in an IT block.
SETEND to access data of different endianness,
for example, to access several big-endian DMA-formatted data fields
from an otherwise little-endian application.
This ARM instruction is available in ARMv6 and above.
This 16-bit Thumb instruction is available in T variants of ARMv6 and above, except the ARMv6-M and ARMv7-M architectures.
There is no 32-bit Thumb version of this instruction.