Galil Motion Control DMC-42 0 Series, User Manual

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To illustrate the complete process, consider the cam relationship described by
the equation:
Y = 0.5 * X + 100 sin (0.18*X)
where X is the master, with a cycle of 2000 counts.
The cam table can be constructed manually, point by point, or automatically by a program. The following program
includes the set-up.
The instruction EAX defines X as the master axis. The cycle of the master is
2000. Over that cycle, Y varies by 1000. This leads to the instruction EM 2000,1000.
Suppose we want to define a table with 100 segments. This implies increments of 20 counts each. If the master
points are to start at zero, the required instruction is EP 20,0.
The following routine computes the table points. As the phase equals 0.18X and X varies in increments of 20, the
phase varies by increments of 3.6 . The program then computes the values of Y according to the equation and

assigns the values to the table with the instruction ET[N] = ,Y.
INSTRUCTION INTERPRETATION
#SETUP Label
EAX Select X as master
EM 2000,1000 Cam cycles
EP 20,0 Master position increments
N = 0 Index
#LOOP Loop to construct table from equation
P = N

3.6 Note 3.6 = 0.18 * 20
S = @SIN [P]*100 Define sine position
Y = N*10+S Define slave position
ET [N] =, Y Define table
N = N+1
JP #LOOP, N<=100
Repeat the process
EN
Now suppose that the slave axis is engaged with a start signal, input 1, but that both the engagement and
disengagement points must be done at the center of the cycle: X = 1000 and Y = 500. This implies that Y must be
driven to that point to avoid a jump.
This is done with the program:
INSTRUCTION INTERPRETATION
#RUN Label
EB1 Enable cam
PA,500 starting position
SP,5000 Y speed
BGY Move Y motor
AM After Y moved
AI1 Wait for start signal
EG,1000 Engage slave
AI - 1 Wait for stop signal
EQ,1000 Disengage slave
EN End
Command Summary - Electronic CAM
Command Description
EA p Specifies master axes for electronic cam where:
p = X,Y,Z or W or A,B,C,D,E,F,G,H for main encoder as master or M or N a for virtual axis
master
EB n Enables the ECAM
Chapter 6 Programming Motion ▫ 79 DMC-42x0 User Manual