;;; JNZ adr  OF:0/SF:1/ZF:0
MAIN    START
        LD      GR1,A
        AND     GR1,GR1
        JNZ     TO
        LAD     GR1,0
        JUMP    FIN
TO      LAD     GR1,#FFFF
FIN     RET
A       DC      -1
        END