Note that snusp returns value of current memory cell on exit.
This is by design, see spec par 4.2 http://www.quirkster.com/iano/snusp/snusp-1.0-spec-wd1.pdf
This is by design, see spec par 4.2 http://www.quirkster.com/iano/snusp/snusp-1.0-spec-wd1.pdf