I/O Number; Concept Of I/O Number Assignment - Mitsubishi Electric L02SCPU User's Manual And Reference

2.2

I/O Number

This section describes the I/O number assignment required for data communication between the CPU module or its
built-in functions and I/O modules or intelligent function modules.
2.2.1

Concept of I/O number assignment

(1) Purpose of I/O number assignment
I/O numbers can be assigned with any given number for the following purposes.
(a) Reserving points for future module changes
The number of points can be reserved to prevent the I/O number modification when the current module is
changed in the future to the one with the different number of occupied I/O points.
(b) Preventing I/O numbers from being changed
The change in the I/O numbers can be prevented when an I/O module or intelligent function module, whose
occupied I/O points are other than 16, is removed due to failure.
(c) Changing the I/O numbers to those used in the program
When the I/O numbers used in the actual system differ from those in the program, the I/O numbers of each
module can be changed to the ones in the program. If any of the I/O modules whose number of I/O points are
other than 16 fails without I/O assignment setting, the I/O numbers assigned following to the failed module may
change, leading to a malfunction. For this reason, making the I/O assignment setting is recommended.
CHAPTER 2 APPLICATION OF PROGRAMMING
2
41