Mitsubishi MELSEC LJ71C24, User Manual

Page: 332 / 428

App. - 3 App. - 3
APPENDIXES
IMPORTANT
Do not write data in the "System area" of the buffer memory.
If data is written to any of the system areas, the programmable controller system
may malfunction.
Some of the user areas are partially system areas. Care must be taken when
performing read/write to the buffer memory.
POINT
To use the dedicated instructions, change the following initial settings (default
values) for data communications by registration operation from GX Works2 or by
the CSET instruction for the sequence program.
1) Initial settings for communication using the MC protocol
• Setting the unit of data length sent by the on-demand function
"Word/byte units designation" (addresses: 150 (96
H
)/310 (136
H
))
• Setting the buffer memory used by the on-demand function
"Buffer memory head address designation" (addresses: 160 (A0
H
)/320
(140
H
))
"Transmission buffer memory length designation" (addresses: 163
(A3
H
)/323 (143
H
))
2) Initial settings for communication using the nonprocedural/bidirectional
protocols
• Setting the unit of data length to be sent and received
"Word/byte units designation" (addresses: 150 (96
H
)/310 (136
H
))
• Setting the transmission area
"Transmission buffer memory head address designation" (addresses:
162 (A2
H
)/322 (142
H
))
"Transmission buffer memory length designation" (addresses: 163
(A3
H
)/323 (143
H
))
• Setting the reception area
"Receive buffer memory head address designation" (addresses: 166
(A6
H
)/326 (146
H
))
"Receive buffer memory length designation" (addresses: 167 (A7
H
)/327
(147
H
))
For details on the registration operation by GX Works2, refer to Section 7.4.
For details on the CSET instruction, refer to the User's Manual
(Application).