Mitsubishi Electric AJ71C24-S6 User Manual page 99

6. DATA COMMUNICATIONS USING AN M : N MULTIDROP LINK
MELSEC-A
6.3.2 Data communications with PC CPUs by setting a master station and slave stations
One of the computers is set as a master station and the other computers are
set as slave stations which need the approval of the master station to
perform data communications with PC CPUs.
E x a m ~ l e Time
request muniumo
munrallonr
stave station campuler 1
h l
slave station computer 2 ~ e r p o n r e
A p p r o v ~ I
Slave rfafion compvter m-1
Data communications
with PC CPUr
Master station
*
(Before (2))
(station
number 80H)
-
a m -
TrsnsmilB the broadcast
data to ail cornputerr so
that the master station
rtartrlcompletef data
communications with Approval
PC CPUr
1
I
~ a f a
communicationr with P C CPUr
The following example shows how each computer performs data com-
munications with PC CPUs.
After the start of data communications between a computer and PC CPUs,
each computer executes the time-out check of the maximum data corn-
munications time.
A computer at a slave station that is not performing data communications
with a PC CPU checks the communications completed code which is trans-
mitted from the computer when it has completed data communications with
PC CPUs.
In the following figure, the computer at the minimum station number 80H is
set as the master station and other computers are set as slave stations.
+
:
Computers with the access right
+(After (2))
(station
number 81 H)
(Station number24
(station (station
number 87H) number 88H)
(Station number 1 5 4
I @