Galil DMC-13X8 Virtual Axis, Ac, Dc, Jg, Sp, Pr, Pa, Bg, It, Ga, Vm, Vp, Cr, St, Dp, Rp, Bgn

D=C+1
DELTA=XPOS[D]-	Compute the difference
XPOS[C]
DX[C]=DELTA	Store difference in array
C=C+1	Increment index
JP #L,C<500	Repeat until done
#PLAYBCK	Begin Playback
CMX	Specify contour mode
DT2	Specify time increment
I=0	Initialize array counter
#B	Loop counter
CD XPOS[I];WC	Specify contour data
I=I+1	Increment array counter
JP #B,I<500	Loop until done
DT 0;CD0	End contour mode
EN	End program

For additional information about automatic array capture, see Chapter 7, Arrays.

Virtual Axis

The DMC-13X8 controller has an additional virtual axis designated as the N axis. This axis has no encoder and no DAC. However, it can be commanded by the commands:

AC, DC, JG, SP, PR, PA, BG, IT, GA, VM, VP, CR, ST, DP, RP.

The main use of the virtual axis is to serve as a virtual master in ECAM modes, and to perform an unnecessary part of a vector mode. These applications are illustrated by the following examples.

ECAM Master Example

Suppose that the motion of the XY axes is constrained along a path that can be described by an electronic cam table. Further assume that the ecam master is not an external encoder but has to be a controlled variable.

This can be achieved by defining the N axis as the master with the command EAN and setting the modulo of the master with a command such as EMN= 4000. Next, the table is constructed. To move the constrained axes, simply command the N axis in the jog mode or with the PR and PA commands.

For example,

PAN = 2000

BGN

will cause the XY axes to move to the corresponding points on the motion cycle.

Sinusoidal Motion Example

The x axis must perform a sinusoidal motion of 10 cycles with an amplitude of 1000 counts and a frequency of 20 Hz.

This can be performed by commanding the X and N axes to perform circular motion. Note that the value of VS must be

VS=2p * R * F

where R is the radius, or amplitude and F is the frequency in Hz. Set VA and VD to maximum values for the fastest acceleration.

Chapter 6 Programming Motion • 90 USER MANUAL