Galil Motion Control DMC-42 0 Series, User Manual

Page: 145 / 218

MG @IN[17]
the controller will return the state of the least significant bit of block 2 (assuming block 2 is configured as an input).
Example Applications
Wire Cutter
An operator activates a start switch. This causes a motor to advance the wire a distance of 10”. When the motion
stops, the controller generates an output signal which activates the cutter. Allowing 100 ms for the cutting
completes the cycle.
Suppose that the motor drives the wire by a roller with a 2” diameter. Also assume that the encoder resolution is
1000 lines per revolution. Since the circumference of the roller equals 2π inches, and it corresponds to 4000
quadrature, one inch of travel equals:
4000/2π = 637 count/inch
This implies that a distance of 10 inches equals 6370 counts, and a slew speed of 5 inches per second, for example,
equals 3185 count/sec.
The input signal may be applied to I1, for example, and the output signal is chosen as output 1. The motor velocity
profile and the related input and output signals are shown in Figure 7.1.
The program starts at a state that we define as #A. Here the controller waits for the input pulse on I1. As soon as
the pulse is given, the controller starts the forward motion.
Upon completion of the forward move, the controller outputs a pulse for 20 ms and then waits an additional 80 ms
before returning to #A for a new cycle.
INSTRUCTION FUNCTION
#A Label
AI1 Wait for input 1
PR 6370 Distance
SP 3185 Speed
BGX Start Motion
AMX
After motion is complete
SB1 Set output bit 1
WT 20 Wait 20 ms
CB1 Clear output bit 1
WT 80 Wait 80 ms
JP #A Repeat the process
Figure 7.1: Motor Velocity and the Associated Input/Output signals
Chapter 7 Application Programming ▫ 141 DMC-42x0 User Manual
START PULSE I1
MOTOR VELOCITY
OUTPUT PULSE
TIME INTERVALS
move
output
wait ready move