Thank you for your reply.
I read the document but it seems to be for FM3 not FM4.
Does it happen to be any information which indicate that this document and "SK-FM3-48PMC-USBSTICK" could be applicable for FM4 ?
I would like to know whether using "SK-FM3-48PMC-USBSTICK" is practicable for FM4 .
(FM4 "MB9BF564" has ARM Coretx-M4F Core(32bit) which is presumably different from the core of FM3.)
Related to bootloader architecture there is no difference between FM3 and FM4. User just needs to adapt to the device Flash type/sector memory map.