Mitsubishi Electric QJ71C24N User Manual page 194

7 DATA COMMUNICATION USING THE BIDIRECTIONAL PROTOCOL
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POINT
(1) The position and size of the transmission area in the buffer memory can be
changed with GX Configurator-SC in accordance with the specifications of the
external device and the transmission data length. (See Section 9.4.5.)
(a) When changing the position and size of the transmission area in the buffer
memory with GX Configurator-SC, designate as follows:
1) Transmission buffer memory head address designation
Designate the starting address for the area to be used as the
transmission area in the user definable area (address: 400
2600 to 3FFF
H
2) Transmission buffer memory length designation
Designate by addresses the length of the area (0001
used as the transmission area in the user definable area (address:
400 to 1AFF
H
(b) When changing the position and size of the receive area in the buffer
memory, if any of the functions below are used concurrently, make sure
that the addresses of the transmission area do not overlap with the buffer
memory addresses assigned for storing transmission/receive data with the
functions.
1) MC protocol buffer memory read/write function
2) MC protocol on-demand function
3) Non procedure protocol transmission/receive function
4) Bidirectional protocol transmission/receive function
5) Pre-defined protocol function (transmission/reception data storage
area)
6) Communication data monitoring function
(2) Set the size of data per data transmission from the programmable controller
CPU to the external device to be smaller than the size of the transmission data
designation area in the buffer memory.
(Transmission data designation area)  (Size of data portion to be sent from
To transmit data whose size is larger than the transmission data designation area,
increase the transmission area, or divide the transmission data before sending.
).
H
, 2600 to 3FFF ).
H H H
the programmable controller CPU)
MELSEC-Q
to 1AFF ,
H H
to 1A00 ) to be
H H
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