System Variable - Siemens SINUMERIK 840D sl Function Manual

The measured value is the actual value of the axis at the instant in time that the switching
signal programmed in the measuring block occurs (rising / falling edge).
Digital output: Configuration
The following machine data must be set to be able to use digital outputs for simulated
measuring:
● MD10360 $MN_FASTIO_DIG_NUM_OUTPUTS = 1 (number of active digital NCK output
bytes)
● MD13120 $MN_CONTROL_UNIT_LOGIC_ADDRESS = 0 (logical address, SINAMICS-
CU)
Digital output: Setting
The configured digital output can be set in a synchronized action:
WHEN <condition> DO $A_OUT[<number of digital output>] = 1
Examples
Digital output used: MD13230 $MN_MEAS_PROBE_SOURCE = 1
Example 1: Channel-specific measuring in 2 axes
Program code
N10 G01 G90 $A_OUT[1]=0
N15 WHEN $AC_DETW<=10 DO $A_OUT[1]=1
N20 MEAS=1 X100 Y10 F100
Example 2: Axial measurement
Program code
N10 G01 G90 $A_OUT[1]=0
N15 WHEN $AA_IW[X]>=80 DO $A_OUT[1]=1
N20 MEASA[X]=(1,1) X100 F100
8.7.4

System variable

For simulated measuring, the following system variables have the same functionality as for
real measuring:
● $AC_MEA (probe has responded)
● $AA_MEAACT (axial measuring active)
● $AA_MM (acquired probe position (MCS))
● $AA_MM1...4 (probe position 1st – 4th trigger (MCS))
Extended Functions
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
Comment
; Preset digital output 1
; Path residual distance <= 10 => Dig. output 1 = 1
; rising edge, probe 1
Comment
; Preset digital output 1
; Axial setpoint >= 80 => Dig. output 1 = 1
; rising edge, probe 1
M5: Measurement
8.7 Simulated measuring
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