Mitsubishi MELSEC QJ71C24, User Manual

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MELSEC-Q
7 DATA COMMUNICATION USING THE BIDIRECTIONAL PROTOCOL
POINT
(1) The position and size of the receive area in the buffer memory can be changed
with GX Configurator-SC in accordance with the specifications of the external
device and the received data length. (See Sections 9.4.5 and 9.4. 8.)
(a) When changing the position and size of the receive area in the buffer
memory with GX Configurator-SC, specify as follows:
1) Receive buffer memory head address designation
Designate the starting address for the area to be used as the receive
area in the user definable area (address: 400
H
to 1AFF
H
, 2600
H
to
3FFF
H
).
2) Receive buffer memory length designation
Designate by addresses the length of the area (0001
H
to 1A00
H
) to be
used as the receive area in the user definable area (address: 400
H
to
1AFF
H
, 2600
H
to 3FFF
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 receive 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) When sending data to the Q series C24 from the external device, one of the
following two adjustments should be made so that the relationship shown
below is maintained.
1) Reduce the send data size.
2) Increase the receive area.
(Receive data storage area)
≥
(Size of data portion sent from the external device)