Delta AH500 - 10.1.2 I;O Refreshing and Communication Service; 10.2 Operating Modes of the CPU Module; 10.2.1 Operating Modes; 10.2.2 Statuses and Operation under Different Operating Modes

Chapter 10 Operating Principle of the CPU Module
10-3
10.1.2 I/O Refreshing and Communication Service
 I/O refreshing
A CPU module reads external I/O data periodically or output data to external I/O. I/O refreshing includes
the following.
 Refreshing data in a digital I/O module
 Refreshing data in an analog I/O module
 Refreshing data in a network module
 Refreshing data in a motion control module
All I/O refreshing is executed in the same loop. The data in an input device is refreshed before a program
is executed, and the data in an output device is refreshed after the program is executed.
Unit
Maximum data exchange
Data exchange area
Digital I/O module
It depends on the number of input/output
channels in the unit.
Input relay/Output relay
Analog I/O module
It depends on the number of input/output
channels in the unit.
Data register
Network module
It depends on the unit.
Data register
Motion control module
It depends on the unit.
Data register
 Communication service
Communication service is nonscheduled communication service of a network module. It includes the
communication request sent from external equipment to a CPU module, and the communication request
sent from the CPU module to the external equipment.
10.2 Operating Modes of the CPU Module
10.2.1 Operating Modes
There are two operating modes. They can be used to control a user program and all tasks.
STOP mode: A program is not executed under this mode. Users can download a module table, initialize CPU
configuration and other setting, download a program, check a program, and force a bit ON/OFF.
RUN mode: A program is executed under this mode. Users can not download a module table, and initialize
CPU configuration and other setting.
10.2.2 Statuses and Operation under Different Operating Modes
The STOP mode and the RUN mode are modes for a CPU module. The statuses and operation under these
modes are listed below.
 Basic operation
CPU
mode
Program
I/O
refreshing
External output
Program memory
Non-latched
area
Latched
area
STOP
The execution
of the program
stops.
The I/O
refreshing is
executed.
OFF (If users set the I/O
module so that the final
state of the external output
on the I/O module is
retained, the final state of
the external output on the
I/O module will be
retained.)
The data in the program
memories are retained.
RUN
The program is
executed.
The I/O
refreshing is
executed.
The external output is
controlled by the program.
The program memories are
controlled by the program.