118
Message Communications Characteristics
Section 7-2
7-1-4
System Startup Time
This section describes the system startup time for a Network, assuming that
the scan list is enabled and that remote I/O communications are set to start
automatically at startup. The system startup time is the delay from the time
that the Master Unit is turned ON or restarted until the time remote I/O com-
munications begin.
The system startup time when the Master Unit is set to start up immediately
after power supplies of all the slaves’ are turned ON is different from when the
Master Unit is restarted while communications are in progress. The startup
times are shown in the following table.
Program Example
As shown in the preceding table, it takes time for DeviceNet communications
to start up. This programming uses flags in the Master Status Area to prevent
the slaves’ I/O processing from being performed until the Master Unit and
remote I/O communications have started up.
Note Refer to the operation manual of the Master Unit being used for details on the
Master Unit Status Area.
The following program example is for a CS-series PLC and a Master Unit with
a unit number of 00.
7-2
Message Communications Characteristics
7-2-1
Message Communications Time
The message communications time is the time required from the time a Mas-
ter Unit starts to send a message over the Network to another node until the
Master Unit completes sending the message (SEND/RECV instructions to
send/receive data and CMND/IOWR instructions to execute FINS com-
mands).
Note If the CPU Unit attempts to send another message or receives a message
from another node before the message communications time has finished, the
Condition
Slave’s indicator status
System startup
time
The master is started
immediately after slave
startup.
NS indicator is OFF or flashing green. 6 s
The master only is
restarted.
NS indicator is flashing red while the
master is OFF.
8 s
The slaves only are
restarted.
-
10 s
(004)
JMP #0001
(005)
JME #0001
2001
15
2001
14
I/O Data
Communications
Flag
Error/Communic
ations Stopped
Flag
Slave’s I/O
processing
Summary of Contents for E5ZN-DRT
Page 3: ...iv ...
Page 5: ...vi ...
Page 9: ...x ...
Page 15: ...xvi EC Directives 6 ...
Page 83: ...68 Ladder Programming Examples Section 4 5 ...
Page 123: ...108 Sending Explicit Messages Section 6 5 ...
Page 135: ...120 Message Communications Characteristics Section 7 2 ...
Page 157: ...142 Index Unit status 57 85 user set allocations 43 61 V variable types C0 51 C1 51 C3 52 ...
Page 159: ...144 Revision History ...
Page 161: ...E5ZN DeviceNet Communications Unit Cat No H119 E1 01 OPERATION MANUAL ...