Cpu Control Instructions - Automationdirect.com DirectLOGIC DL205 Series User Manual

CPU Control Instructions

No Operation (NOP)
The No Operation is an empty (not programmed) memory location.
230
240
250-1
260
DirectSOFT
DS Used
HPP Used
End (END)
The End instruction marks the termination point of the normal
230
program scan. An End instruction is required at the end of the main
program body. If the End instruction is omitted an error will occur and
240
the CPU will not enter the Run Mode. Data labels, subroutines and
250-1
interrupt routines are placed after the End instruction. The End
260
instruction is not conditional; therefore, no input contact is allowed.
DS Used
DirectSOFT
HPP Used
Stop (STOP)
The Stop instruction changes the operational mode of the CPU from
230
Run to Program (Stop) mode. This instruction is typically used to stop
PLC operation in a shutdown condition such as a I/O module failure.
240
250-1
260
In the following example, when SP45 comes on indicating a I/O module failure, the CPU
will stop operation and switch to the program mode.
DS Used
DirectSOFT
HPP Used
SP45 will turn on
if there is an I/O
module failure.
Chapter 5: Standard RLL Instructions - CPU Control
NOP
END
SP45
STOP
Handheld Programmer Keystrokes
N O
SHFT
TMR INST#
Handheld Programmer Keystrokes
E N
SHFT
4 TMR
Handheld Programmer Keystrokes
$ SP E
SHFT
STR STRN
S T O
SHFT SHFT
RST MLR INST#
DL205 User Manual, 4th Edition, Rev. B
NOP
P
ENT
CV
END
D
ENT
3
STOP
F
ENT
4 5
P
ENT
CV
1
2
3
4
5
6
7
8
9
10
11
12
13
14
A
B
C
D
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