Filter
Top Products
124 • Chapter 7 Application Programming DMC-3425
Automatic Subroutines for Monitoring Conditions
Often it is desirable to monitor certain conditions continuously without tying up the host or DMC-3425
program sequences. The DMC-3425 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, and having an application program actively executing on the controller. The
pre-defined labels are:
SUBROUTINE DESCRIPTION
#LIMSWI Limit switch on any axis goes low
#ININT Input specified by II goes low
#POSERR Position error exceeds limit specified by ER
#MCTIME Motion Complete timeout occurred. Timeout period set by TW command
#CMDERR Bad command given
#TCPERR Ethernet Communication Error
The following examples illustrate the use of the automatic subroutines:
Example - Limit Switch:
This simple program prints a message upon the occurrence of a limit switch. For the #LIMSWI sub-
routine to execute, the DMC-3425 must be executing an applications program from memory and the
controller must be commanding the motor to move. The RE command is used to return from the
#LIMSWI subroutine. The #LIMSWI subroutine will be re-executed if the limit switch remains active.
Instruction
Interpretation
#LOOP Dummy Program
JP #LOOP;EN Jump to Loop
#LIMSWI Limit Switch Label
MG "LIMIT OCCURRED" Print Message
RE Return to main program
Example - Position Error
Instruction Interpretation
:ED Edit Mode
000 #LOOP Dummy Program
001 JP #LOOP;EN Loop
002 #POSERR Position Error Routine
003 V1=_TEA Read Position Error
004 MG "EXCESS POSITION ERROR" Print Message
005 MG "ERROR=",V1= Print Error
006 RE Return from Error
<control> Q Quit Edit Mode
:XQ #LOOP Execute Dummy Program
:JG 100000 Jog at High Speed
:BGA Begin Motion