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Checking Operations of CS-series and CJ-series Master Units
Section 6-3
6-3-4
Checking Normal Operations Using Ladder Programming
This section provides information on how to write a ladder program to monitor
the operation of the CompoBus/S System and prohibit using the I/O data of
the Slaves in the system when an error occurs or the Slaves are not partici-
pating in the network correctly.
Master Unit Settings
The following table shows the Master Unit settings used in the programming
example (when all Slaves OUT0 to OUT15 and IN0 to IN15 are connected).
Example 1
Communications will be performed only when the Communications Error
Flags of all Slaves are OFF, and the Active Node Flags correspond to the con-
figuration of connected Slaves.
Status Area
(Refer to
on page 97 and page 119 for details.)
Active Node Flags:
Once a Slave joins the CompoBus/S network after the Slave is turned ON, the
Active Node Flag corresponding to the Slave will be ON.
Communications Error Flags:
If a Slave in the network fails to communicate with the Master, the Communi-
cations Error Flag corresponding to the Slave will be ON. After the Communi-
cations Error Flag is ON, the previous input data from the input Slave will be
kept on hold. While the Communications Error Flag is ON, the input data of
the input Slave is not reliable. (The program will be executed with the previous
data.)
Operations
The input conditions require the Input Slave and Output Slave Active Node
Flags to match the network configuration and that the Output Slave or Input
Slave Communications Error Flags are OFF.
Master’s unit number
0
Usable node numbers
IN0 to IN15 and OUT0 to OUT15
CIO 2016
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
0
Output Slave Communications Error Flags
Slave 7
0
Active Output Slave Flags
Slave 7
0
CIO 2017
Bits
Input Slave Communications Error Flags
Slave 7
0
Active Input Slave Flags
Slave 7
0
CIO 2018
Output Slave Communications Error Flags
Slave 15
8
Active Output Slave Flags
Slave 15
8
CIO 2019
Input Slave Communications Error Flags
Slave 15
8
Active Input Slave Flags
Slave 15
8