Table of Contents
Advertisement
7
PARAMETER SETTING
7 - 18
(b)
The QJ71MT91 starts the CPU response monitoring timer when it receives
a request message from the master. (1) in the figure)
The CPU response monitoring timer monitors the programmable controller
CPU processing until the QJ71MT91 starts sending a response message to
the master. (2) in the figure)
(c)
When the CPU response monitoring timer reaches the preset time, the
QJ71MT91 performs the following processings. (3) in the figure)
1)
Issues the error code: 7380
2)
Issues the exception code: 04
*1: Refer to Section 11.3.3 for details of the error code.
*2: Refer to Section 11.3.2 for details of the exception code.
POINT
When the CPU response monitoring timer value is "0ms", the QJ71MT91 waits until
the programmable controller CPU completes processing. (Limitless waiting)
(4) Preferred node specification
(a) Relationship between preferred node specification and TCP
connection opening and closing
1)
The QJ71MT91 opens and closes TCP connections automatically.
2)
The QJ71MT91 can open up to 64 TCP connections simultaneously.
3)
Before opening a new TCP connection in addition to already open 64
TCP connections, the QJ71MT91 automatically closes the TCP
connection that has not communicated for the longest time among the
non-communicating ones.
At this time, the TCP connections with the target devices specified as
the preferred nodes are not closed.
4)
If the number of TCP connections used by the QJ71MT91 exceeds 64,
specify the preferred nodes for the target devices that must keep the
TCP connections open.
5)
Up to 64 preferred nodes can be specified.
(b) Preferred node specification: IP address
1)
Set the IP address of the target device to be specified for the preferred
node.
2)
Set the value that satisfies the following conditions.
Condition 1: The IP address class is any of A, B and C.
Condition 2: The host address bits are not all "0" or all "1".
(c) Preferred node specification: TCP connection
1)
Specify the number of TCP connections used for communication with
the specified preferred nodes.
2)
Set the value that satisfies the following condition.
(Preferred node specification 1: TCP connection + ... + preferred node
specification 64: TCP connection) + number of TCP connections for
GX Developer connection ≤ 64
POINT
It is not necessary to use the preferred node specification when the total number of
TCP connections used by the QJ71MT91 is not more than 64.
. *1
H
to the master side. *2
H
MELSEC-Q
7 - 18
Advertisement
Table of Contents
