CODE (loop)
PC ORG @ 0x45 + ! ( stable ABI JP )
    0 IX+ INC(IXY+), IFZ, 1 IX+ INC(IXY+), THEN, ( I++ )
    ( Jump if I <> I' )
    A 0 IX+ LDrIXY, 2 IX- CP(IXY+), JRNZ, L1 BWR ( branch )
    A 1 IX+ LDrIXY, 1 IX- CP(IXY+), JRNZ, L1 BWR ( branch )
    ( don't branch )
    IX DECd, IX DECd, IX DECd, IX DECd,
    BC INCd,
;CODE