Chapter 6 Programming Motion • 98 USER MANUAL
MCX
WT100; 'STABILIZE
JP#LOOP; 'KEEP CORRECTING UNTIL ERROR IS WITHIN 'TOLERANCE
#END; 'END #CORRECT SUBROUTINE, RETURNING TO CODE
SPX=spx
EN
Dual Loop (Auxiliary Encoder)
The DMC-13X8 provides an interface for a second encoder for each axis except for axes configured
for stepper motor operation and axis used in circular compare. When used, the second encoder is
typically mounted on the motor or the load, but may be mounted in any position. The most common
use for the second encoder is backlash compensation, described below.
The second encoder may be a standard quadrature type, or it may provide pulse and direction. The
controller also offers the provision for inverting the direction of the encoder rotation. The main and
the auxiliary encoders are configured with the CE command. The command form is CE x,y,z,w where
the parameters x,y,z,w each equal the sum of two integers m and n. m configures the main encoder
and n configures the auxiliary encoder.

Using the CE Command

m= Main Encoder n= Second Encoder
0 Normal quadrature 0 Normal quadrature
1 Pulse & direction 4 Pulse & direction
2 Reverse quadrature 8 Reversed quadrature
3 Reverse pulse & direction 12 Reversed pulse & direction
For example, to configure the main encoder for reversed quadrature, m=2 , and a second encoder of
pulse and direction, n=4, the total is 6, and the command for the X axis is
CE 6

Additional Commands for the Auxiliary Encoder

The command, DE x,y,z,w, can be used to define the position of the auxiliary encoders. For example,
DE 0,500,-30,300
sets their initial values.
The positions of the auxiliary encoders may be interrogated with the command, DE?. For example
DE ?,,?
returns the value of the X and Z auxiliary encoders.
The auxiliary encoder position may be assigned to variables with the instructions
V1= _DEX
The command, TD XYZW, returns the current position of the auxiliary encoder.
The command, DV XYZW, configures the auxilliary encoder to be used for backlash compensation.