4.4.4 REV, REVH, and REVSH
REV reverses the byte order in a data word,
For example, if R0 is 0x12345678, in executing the following:
REV R1, R0
R1 will become 0x78563412,
The Definitive Guide to the ARM® Cortex-M3 by Joseph Yiu
in a C file
Would call this assembler instruction in a function ?
or define it as a macro ?
or inline assembler ?