Galil Motion Control DMC-42 0 Series, User Manual

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Note: The NO command is an actual controller command. Therefore, inclusion of the NO commands will require
process time by the controller.
Difference between NO and ' using the GalilTools software
The GalilTools software will treat an apostrophe (') commend different from an NO when the compression
algorithm is activated upon a program download (line > 80 characters or program memory > 4000 lines). In this
case the software will remove all (') comments as part of the compression and it will download all NO comments to
the controller.
Executing Programs - Multitasking
The DMC-42x0 can run up to 8 independent programs simultaneously. These programs are called threads and are
numbered 0 through 7, where 0 is the main thread. Multitasking is useful for executing independent operations
such as PLC functions that occur independently of motion.
The main thread differs from the others in the following ways:
1. Only the main thread, thread 0, may use the input command, IN.
2. When input interrupts are implemented for limit switches, position errors or command errors, the
subroutines are executed as thread 0.
To begin execution of the various programs, use the following instruction:
XQ #A, n
Where n indicates the thread number. To halt the execution of any thread, use the instruction
HX n
where n is the thread number.
Note that both the XQ and HX commands can be performed by an executing program.
The example below produces a waveform on Output 1 independent of a move.
#TASK1
Task1 label
AT0 Initialize reference time
CB1 Clear Output 1
#LOOP1 Loop1 label
AT 10 Wait 10 msec from reference time
SB1 Set Output 1
AT -40 Wait 40 msec from reference time, then initialize reference
CB1 Clear Output 1
JP #LOOP1
Repeat Loop1
#TASK2 Task2 label
XQ #TASK1,1 Execute Task1
#LOOP2 Loop2 label
PR 1000 Define relative distance
BGX Begin motion
AMX After motion done
WT 10 Wait 10 msec
JP #LOOP2,@IN[2]=1
Repeat motion unless Input 2 is low
HX Halt all tasks
The program above is executed with the instruction XQ #TASK2,0 which designates TASK2 as the main thread (i.e.
Thread 0). #TASK1 is executed within TASK2.
Chapter 7 Application Programming ▫ 104 DMC-42x0 User Manual