o<myspindlespeeddown> sub
   o10 if [#<_spindle_on> EQ 1]
      O20 if [#<_rpm> GT 100]
         #<speed-cmd> = [#<_rpm> - 100] 
      O20 else 
         #<speed-cmd> = 0
         M5
      O20 endif
      S#<speed-cmd>
   o10 endif
o<myspindlespeeddown> endsub
M2