A thesis by Jian – Xiong Shao, 1983, titled OUP/M – A 6502 Operating system, contains a floppy disk based operating system for the 6502. It is modelled after CP/M and follows the same design principles.
In the development of OUP/M, an OSI C-3 microcomputer system was used. This system consists of a 6502 CPU, a dual 8-inch floppy disk drive, a console, a printer, and 56 K bytes of RAM.
On this machine all I/O is memory mapped and address space layout has to be taken into consideration.

For years only the document was available, archived on archive.org, with the source in the document.
Jian – Xiong Shao did not publish more 6502 code, further implementations are unknown.

A revival

In 2018, a thread on the osiweb.org forum appeared, user KIball, Charles Mangin, option8, typed in the sources and tested it on an emulated OSI C3.
The results are published on his github.

	OUP/M – A 6502 CP/M Operating system, A thesis by Jian – Xiong Shao, 1983,
	Sources by Charles Mangin
	Assembled and emulator by KLYball, from the osiweb thread
	CP_M clone for OSI CIII – thread osiweb.org