Mitsubishi MELSEC LJ71C24, Руководство пользователя

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11 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 Works2 in accordance with the specifications of the external device
and the received data length. (Refer to Section 7.2.)
(a) When changing the position and size of the receive area in the buffer
memory with GX Works2, 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 setting 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 setting 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) Predefined protocol function (Transmission/reception data storage
area)
4) Nonprocedural protocol transmission/receive function
5) Bidirectional protocol transmission/receive function
6) Communication data monitoring function
(2) Set the size of data per data transmission from the CPU module 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
the CPU module)
To transmit data whose size is larger than the transmission data designation
area, increase the transmission area, or divide the transmission data before
sending.