Omron SYSMAC CVM1 Series Operation Manual page 82

Index and Data Registers (IR and DR)
64
An auto-decrement decreases the contents of an Index Register by 1 or 2 before
executing the instruction. A"–" prefix indicates an auto-decrement of 1, and a
"––" prefix indicates an auto-decrement of 2. The notation for auto-increments
and auto-decrements is as follows:
,IRn+: After execution, increase the contents of IRn by 1.
,IRn++: After execution, increase the contents of IRn by 2.
,–IRn: Decrease the contents of IRn by 1 before execution.
,––IRn: Decrease the contents of IRn by 2 before execution.
Both an auto-increment and an auto-decrement are used in the following exam-
ple. The data movement for the first execution is shown. The second execution
would move the contents of CIO 1902 to CIO 1898; the third execution would
move the contents of CIO 1904 to CIO 1897; etc.
(030)
MOV IR0++ IR1–
Word Content
CIO 1900 08FC
CIO 1900
Register Content
IR1 076C
IR0 076C
Section 3-10
Word Content
CIO 1899 08FC
CIO 1900 – 1