N = Number of iterations.  (Excluding a N value defaults iteration count to 1)

This command places all the fibres in a circle of the smallest possible  radius. This fibre radius is ... Before attempting to move any fibres, the command checks whether an AFSETUP, AFALLCIRCLE or AFALLPARK is in :  already progress and takes appropriate action. The fibreK  back-illumination is switched on before any fibres are moved and switched  off again on completion. The robot is also parked on successful  completion.  The optional iteration count given on invocation of the AFALLCIRCLE  command is only used for the circle fibre placement. On completion or  abort the initial fibre iteration count is set.