GlossarySpecial functions: AppendixFunction Manual, 11/2006, 6FC5397-2BP10-2BA0 33Software limit switchSoftware limit switches limit the traversing range of an axis and prevent an abrupt stop of theslide at the hardware limit switch. Two value pairs can be specified for each axis andactivated separately by means of the → PLC.Spline interpolationWith spline interpolation, the controller can generate a smooth curve characteristic from onlya few specified interpolation points of a set contour.Standard cyclesStandard cycles are provided for machining operations, which are frequently repeated:• Cycles for drilling/milling applications• for turning technologyThe available cycles are listed in the "Cycle support" menu in the "Program" operating area.Once the desired machining cycle has been selected, the parameters required for assigningvalues are displayed in plain text.SubblockBlock preceded by "N" containing information for a sequence, e.g., positional data.SubprogramSequence of statements of a → part program that can be called repeatedly with differentdefining parameters. The subroutine is called from a main program. Every subprogram canbe protected against unauthorized read-out and display. → Cycles are a form of subroutines.Supply SystemA network is the connection of multiple S7-300 and other end devices, e.g., a programmingdevice via a → connecting cable. A data exchange takes place over the network between theconnected devices.SynchronizationStatements in → part programs for coordination of sequences in different → channels atcertain machining points.