Internal Data Structures - Omron CQM1-ARM21 Operation Manual

Internal Data Structures

4-2 Internal Data Structures

CQM1 CPU
Control Bits
Status Flags
Setup Mode Commands
Change_Slave_Address
Read_Actual_Configuration
Set_Permanent_Configuration
Get_Permanent_Configuration
Get_Permanent_Parameter
Set_Permanent_Parameter
Read_Parameter
Write_Parameter
An AS-Interface master uses several lists to keep track of the
communication between the master and the slaves and to exchange data
with the PLC CPU. Data that is used to describe the desired configuration
of the AS-I system is stored in non-volatile memory.
The figure below shows an overview of the master's lists, and shows how
data is transferred between the CQM1 CPU, these lists, and the slaves.
For normal operation of the CQM1-ARM21, knowledge of its internal data
structures is not essential, but it may help to better understand specific
functions.
Thin lines indicate that data of one particular slave is transferred.
Thick lines indicate all data is transferred at once.
Each I/O refresh
IR out
IR in
LPS
PCD
PP
ODI Output Data Image.
This array contains the data to be transmitted to the active slaves
at the next data exchange.
IDI Input Data Image.
This array contains the latest actual copies of the received data
from the inputs of all active slaves. Input data of inactive slaves is
set to zero (0).
LDS List of Detected Slaves.
In this list one bit is set for each slave (0...31) that is detected by
the master (through the start-up operation or inclusion phase).
LAS List of Activated Slaves.
In this list one bit is set for each slave (1...31) that has been acti-
vated during start-up operation or inclusion phase.
LPS List of Projected Slaves.
This list contains all slaves (1...31) expected in the AS-Interface
system. The list is created either by local configuration of the
master using Set_Permanent_Configuration commands, or copied
ODI
IDI
Flags
SET switch OFF→ ON
LAS
SET switch OFF→ON
CDI
SET switch OFF→ON
PI
At initialisation
Section 4-2
All active slaves
Continuous checking
At slave At slave
LDS
activation detection
At slave detection
At slave activation
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