Special Instructions - Automation Direct DL05 User Manual

Chapter 9: Maintenance and Troubleshooting

Special Instructions

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There are several instructions that can be used to help you debug your program during
machine startup operations.
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• END
• PAUSE
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• STOP
END Instruction: If you need a way to quickly disable part of the program, just insert an
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END statement prior to the portion that should be disabled. When the CPU encounters the
END statement, it assumes that is the end of the program. The following diagram shows an
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example.
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7
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9
0
PAUSE Instruction: This instruction provides a quick way to allow the inputs (or other logic)
to operate while disabling selected outputs. The output image register is still updated, but the
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output circuits are not. For example, you could make this conditional by adding an input
contact or CR to control the instruction with a switch or a programming device. Or, you
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could just add the instruction without any conditions so the selected outputs would be
disabled at all times.
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B
C
STOP Instruction: Sometimes during machine startup you need a way to quickly turn off all
the outputs and return to Program Mode. You can use the STOP instruction. When this
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instruction is executed the CPU automatically exits Run Mode and enters Program Mode.
Remember, all outputs are turned off during Program Mode. The following diagram shows an
example of a condition that returns the CPU to Program Mode.
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DL05 Micro PLC User Manual, 6th Edition, Rev. A
Normal Program
X0 X2
X1 X3 X4
X10
Normal Program
X0 X2
X1 X3 X4
X10
New END disables X10 and Y1
Y0
X0
X1
Y1
X10
END
PAUSE disables Y0 and Y1
Y0
X0
Y1
X1
X10
END
X2 Y0
X3 X4
END
Y1
END
Y0 – Y1
PAUSE
X2 Y0
X3 X4
Y1
END