org    start

          temp   equ r-1

r         dat    55,            89
s         dat    1,             0
t         dat    0,             1

euclidext mov    r,             temp
          div.ab temp,          temp
          mov.ba temp,          temp
          mul    s,             temp
          sub    temp,          t

          mov    s,             temp
          mov    t,             s
          mov    temp,          t

          mod.ab r,             r
          mov.x  r,             r
start     jmn.a  euclidext,     r