bash - need a shell script to convert big endian to little endian -

i need shell script program print hexadecimal number big endian little endian

for example

my virtual address = 00d66d7e , should input function , should return 7e6dd600 , need sample bash script

thank in adavance

for 32 bit addresses, assuming it's 0 padded:

v=00d66d7e  echo ${v:6:2}${v:4:2}${v:2:2}${v:0:2} # 7e6dd600

And