Emerson 0471-0128-02 manual 2 0x60C1 Interpolationdatarecord, 3 0x60C2 Interpolationtimeperiod

7.4.20x60C1 Interpolation_data_record

This object is used to specify the target position. Linear interpolation is used to generate position demand values every 250µs. The position is specified in user-defined position units. The value is written into sub-index 1.

Table 7.33 0x60C1 Interpolation_data_record

0x60C1	Interpolation_data_record
Sub-index 0
Access: RO		Range: N/A	Size: Unsigned 8	Unit: N/A
Default:	1
Description:	This object is used to specify the target position.
Sub-index 1
Access: RW		Range: 0 to 0xFFFFFFFF	Size: Unsigned 32	Unit: N/A
Default:	N/A
Description:	The set-point

7.4.30x60C2 Interpolation_time_period

Table 7.34 Interpolation_time_period

0x60C2	Interpolation_time_period
Sub-index 0
Access: RO		Range: N/A	Size: Unsigned 8	Unit: N/A
Default:	2
Description:	The number of last sub-indexes in this object.
Sub-index 1
Access: RW		Range: 0 to 255	Size: Unsigned 8	Unit: (sub-index 2)
Default:	250 (units are dependant on the value in sub-index 2)

Description: The number of time units between interpolator re-starts. A time unit is defined by sub-index

2.The interpolator time period value is checked to ensure that it is valid. Valid values are 250µs, 500µs or any multiple of 1ms. An attempt to write other values results in an SDO Abort code.

Sub-index 2

Access: RW		Range: -6 to 0	Size: Signed 8	Unit: N/A
Default:	-6 (a time unit of 1µs)

Description: This specifies the time unit for the interpolation time period. Sub-index 2 specifies the unit exponent. The time unit, therefore, is 10(sub-index 2). The range of values allows for the shortest time unit to be 1µs, and the longest to be 1s.

The implementation of interpolated position mode allows synchronous operation only, where a fixed, common interpolation interval is defined. The time specified must always be an integer multiple of the control loop cycle time. The time period index has a minimum value of -6 (i.e. the smallest time unit will be microseconds), see Table 7.35 for more information.

Table 7.35 Interpolation time period units

Value in 0x60C2, sub-index 2	Description
0	1 second
-1	0.1 of a second
-2	0.01 of a second
-3	0.001 of a second
-4	0.0001 of a second
-5	0.00001 of a second
-6	0.000001 of a second

40	SM-EtherCAT User Guide
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