Maximum path for pre-output of M functions (P-CHAN-00604)


Maximum path for pre-output of M functions


This parameter sets an additional limitation of the look-ahead range for the pre-output of M functions (see [FCT-C1]) to a maximum distance.

If this maximum distance exceeds the sum of all currently considered motion blocks (except for the ‘oldest’ motion block), the ‘oldest’ motion block is output. In other words, an M function can be pre-output by at least the specified distance.



Data type


Data range

0 ... MAX(UNS32)



Default value



Parameter is available as of the following Builds: V2.11.2040.04 ; V2.11.2810.02 ; V3.1.3079.17 ; V3.1.3107.10

If the maximum number of blocks P-CHAN-00603 is set to a high value, it may cause a long delay in channel reaction. To avoid this, a distance limit can also be specified. With long motion blocks in particular, this maximum distance is already reached after a few blocks. This prevents additional delay caused by saving motion blocks in the pre-output of M functions.

Without an explicit specification, the range is not additionally limited (only by the number of blocks P-CHAN-00603).

If a pre-output is set greater than the distance currently saved in the look-ahead range, the M function is pre-output at the maximum known path position and a warning is issued.

Parameterisation example:

configuration.path_preparation.function FCT_DEFAULT | FCT_M_PRE_OUTPUT

configuration.path_preparation.m_pre_output_lookahead 100

configuration.path_preparation.m_pre_output_max_distance 35000 [0.1µm]

Programing Example


Maximum distance for pre-output of M functions


N01 G00 G90 X0 Y0

N02 G01 F10000

'MOS' = '1'

N01 V.G.M_FCT[100].PRE_OUTP_PATH = 28.6 (* in mm *)

N02 V.G.M_FCT[100].SYNCH = 'MOS'

N20 G91 Y1

N21 Y1 ; -> MicroJoint at Y1.4 mm

N43 Y1

N44 Y1

N45 Y1

; Warning 120693: -> MicroJoint due to distance limitation 3.5mm

N46 Y1

N47 Y1

N48 Y1

N49 Y1

N50 M100

N99 M30

Distance-related limiting of pre-output to maximum look-ahead range.
Distance-related limiting of pre-output to maximum look-ahead range.