Yaskawa LEGEND-MC - Manual (Page 306)

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LEGEND-MC User’s Manual
Stack Manipulation
It is possible to manipulate the subroutine stack by using the ZS command. Every time a JS instruction,
interrupt or automatic routine (such as #POSERR or #LIMSWI) is executed, the subroutine stack is
incremented by 1. Normally the stack is restored with an EN instruction. Occasionally it is desirable not to
return back to the program line where the subroutine or interrupt was called. The ZS1 command clears 1
level of the stack. This allows the program sequencer to continue to the next line. The ZS0 command
resets the stack to its initial value. For example, if a limit occurs and the #LIMSWI routine is executed, it
is often desirable to restart the program sequence instead of returning to the location where the limit
occurred. To do this, give a ZS command at the end of the #LIMSWI routine.
Auto Start Routine
If the #AUTO label is included in a Burned Program (BP command), the controller will start executing the
program starting at the location of the #AUTO label when power is applied.
Automatic Subroutines for Monitoring Conditions
Often it is desirable to monitor certain conditions continuously without tying up the host or LEGEND-MC
program sequences. The LEGEND-MC can monitor several important conditions in the background.
These conditions include checking for the occurrence of a limit switch, a defined input, position error, or a
command error. Automatic monitoring is enabled by inserting a special, predefined label in the
applications program. The pre-defined labels are:
CB1 Clear Output Bit 1 (pick up pen)
VP 1000,1000;LE;BGS;AMS Define vector position; move pen
SB1 Set Output Bit 1 (put down pen)
JS #SQUARE;CB1 Jump to square subroutine
EN End Main Program
#SQUARE Square subroutine
V1=500;JS #L Define length of side
V1=-V1;JS #L Switch direction
EN End subroutine
#L;PR V1,V1;BGX Define X,Y; Begin X
AMX;BGY;AMY After motion on X, Begin Y
EN End subroutine
#AUTO Auto start program on power-up
#CMDERR Bad command given
#COMINT Communication interrupt occurred
#ININT Input specified by II goes low
#LIMSWI Limit switch on any axis goes low