CODE (?br)           ( 0x67 )
    HL POPqq,
    HLZ,
    JRZ, L2 BWR ( BR + 2. False, branch )
    L1 BSET ( loop will jump here )
    ( True, skip next 2 bytes and don't branch )
    IY INCss, IY INCss,
    JPNEXT, NOP, NOP, NOP,
CODE (loop) ( 0x77 )
    0 IX+ INC(IXY+), IFZ, 1 IX+ INC(IXY+), THEN, ( I++ )
    ( Jump if I <> I' )
    A 0 IX+ LDrIXY, 2 IX- CP(IXY+), JRNZ, L2 BWR ( branch )
    A 1 IX+ LDrIXY, 1 IX- CP(IXY+), JRNZ, L2 BWR ( branch )
    ( don't branch )
    IX DECss, IX DECss, IX DECss, IX DECss, JR, L1 BWR
