Mitsubishi Electric Melsec QJ71LP21 - Transient Transmission Function (Non-Periodical Communication)

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MELSEC-Q
7 APPLICATION FUNCTIONS
7.4 Transient Transmission Function (Non-Periodical Communication)
The transient transmission function performs data communication only when it is
requested between stations.
The transient transmission function can be requested with the dedicated link
instructions (SEND, RECV, READ, SREAD, WRITE, SWRITE, REQ, ZNRD, ZNWR,
RECVS, RRUN, RSTOP, RTMRD and RTMWR), GX Developer, the intelligent
function module, etc.
In the MELSECNET/H, data communication can be performed with other stations
having the same network number (the same network as where the host is connected),
as well as with stations having other network numbers.
1) Transient transmission function to a station on the same network
GX Developer
1N
S
2
1M
P
1
1N
S
51N
S
6
1N
S
3
1N
S
4
Network No. 1
2) Transient transmission to stations on other networks (routing function)
In this case, the routing parameters must be set for the request source
and relay stations.
GX Developer
1M
P
11N
S
21N
S
3
1N
S
6
1N
S
5
Network No. 1
Request
source
1N
S
42M
P
1
Relay station
3M
P
1
Network No. 3
Request
destination
3N
S
42N
S
3
3N
S
2
3N
S
3
2N
S
2
Network No. 2
Stations for which the routing
parameters are set
Required
Required
Required
Relay station