Omron CP - PROGRAMMING MANUAL 05-2007 - Page 43

10
Programming Concepts Section 1-1
Specifying
an indirect
address
using a reg-
ister
DR offset The bit or word with the PLC memory
address in IR@ + the contents of DR@ is
specified.
Specify DR@ ,IR@. DR (data register)
contents are treated as signed-binary
data. The contents of IR@ will be given a
negative offset if the signed binary value
is negative.
DR0 ,IR0
DR0 ,IR1
Loads the bit with the PLC memory
address in IR0 + the value in DR0.
Stores #0001 in the word with the PLC
memory address in IR1 + the value in
DR0.
Auto Incre-
ment
The contents of IR@ is incremented by
+1 or +2 after referencing the value as
an PLC memory address.
+1: Specify ,IR@+
+2: Specify ,IR@ + +
Note The auto increment operation will
not be executed for a CP1L CPU
Unit if a P_ER or P_AER error
occurs during instruction execu-
tion.
,IR0 ++
,IR1 +
Increments the contents of IR0 by 2
after the bit with the PLC memory
address in IR0 is loaded.
Increments the contents of IR1 by 1
after #0001 is stored in the word with
the PLC memory address in IR1.
Auto Dec-
rement
The contents of IR@ is decremented by
–1 or –2 after referencing the value as
an PLC memory address.
–1: Specify ,–IR@
–2: Specify ,– –IR@
Note The auto decrement operation will
not be executed for a CP1L CPU
Unit if a P_ER or P_AER error
occurs during instruction execu-
tion.
,– –IR0
,–IR1
After decrementing the contents of IR0
by 2, the bit with the PLC memory
address in IR0 is loaded.
After decrementing the contents of IR1
by 1, #0001 is stored in the word with
the PLC memory address in IR1.
Operand Description Notation Application examples
DR0,IR
0
MOV(021)
#1
DR0 ,IR1
,IR0 ++
MOV(021)
#1
,IR1 +
,−−IR
MOV(021)
#1
,−IR1