While it is possible to have CP/M reside in system that has only non-volatile RAM, Most CP/M system have a mass storage device in form of floppy disk, hard disk, and/or flash disk.  The Z80SBC64 is designed with a compact flash disk interface.  The hardware addition is simple, just solder a IDE44 adapter to the CF interface and Voila, we now have the CP/M capability.

CP/M software, however, is quite a bit more involved.  Fortunately a system integration guide for porting CP/M to specific hardware is still readily available from Internet.  http://cpm.z80.de/ is a well-know repository of CP/M for Z80 and other processors.  It is not my intention to provide a tutorial on porting CP/M to Z80, but I do want to describe certain CP/M related functions specific to Z80SBC64 in next project.