Mitsubishi Electric MELSEC iQ-RJ71C24-R4 - Page 374

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18 DATA COMMUNICATIONS BETWEEN TARGET DEVICE AND CPU MODULE IN M:N BASIS
18.3 Examples of Procedure for Data Communications with CPU Module
Ex.
 The target device that has communicated data with the CPU module, or a target device that does not need to communicate
data with the CPU module transmits the data for transferring the line ownership to the target device with the next station
number. A message structure example is shown in .
When a response message (refer to  in this section) is not received from the next target device to which the line ownership
to be passed, data transmission for transferring the line ownership to the target device with the next station number is
repeated until the line ownership is transferred.
 The target device that receives the line ownership transmits a response message to the target device that passes it the line
ownership.
Ex.
*1 Command "ZZ" is a command for description purpose. Determine the command to transfer/obtain the line ownership at the user side.
 The target device that accepted the line ownership by transmitting the response message performs the processing from
.
 When the line usage time of the target device that currently has the line ownership exceeds the maximum data
communications time,
• The target device, which has the next station number, transmits all of the other devices excluding the CPU module station
the general report data and obtains the line ownership and performs the processing.
Õ
Ö
×
CPU CPU CPU
C24 C24 C24 C24
CPU
(Before Ö) (Before Ö)
Target device Target device Target device Target device
(Station No.:1BH) (Station No.:1CH) (Station No.:1DH) (Station No.:1EH)
Data communications
with arbitrary
CPU module
(Station No.:0H)
(Station No.:15H)
(Station No.:2H)
(Station No.:1H)
: Target device that obtained the line ownership
The above C24 includes Q series C24, L series C24, QC24(N), and UC24.
(1C) (1B) (ZZ) (CD)(2)(;)
(1C)
31H 43H
(1B)
31H 42H
(:)
31H 43H 31H 42H 5AH 5AH 43H 44H32H3BH
3AH
*1
Message of Õ above
Transmission destination station No.
Transmission source station No.
Command
Message wait
Sum check code
Target
device
that
transfers line
ownership
(1BH)
Transmission destination station No. Transmission source station No.
Target
device
passed line
ownership
(1CH)
Message of Ö