Mitsubishi Electronics AJ65bt-r2 ユーザーズマニュアル
7 - 9
MELSEC-A
7 USING FRAMES WHEN EXCHANGING DATA
POINT
(1) If there are one or more combinations (1) to 4) in combination table) with a reception head frame
designated, set the reception end data size (
R 2
111
H
) to match the length of the random data
section to be received.
If the reception head frame is designated, the data between the received end frame or the reception
end data size data and the next head frame will not be stored in the R2 reception area. (The data will
be ignored.)
If the reception head frame is designated, the data between the received end frame or the reception
end data size data and the next head frame will not be stored in the R2 reception area. (The data will
be ignored.)
Reception
data
data
Registration frame
(reception head frame)
(reception head frame)
Random data section
or reception end frame
or reception end frame
Not stored in
reception area
reception area
Not stored in
reception area
reception area
Reception
data
data
(2) Make sure not to include data with the same arrangement as the reception head frame and reception
end frame in the random data section.
If data with the same arrangement as the reception head frame or reception end frame is contained
in the random data section, the R2 may incorrectly recognize that data as the reception head frame
or reception end frame.
If data with the same arrangement as the reception head frame or reception end frame is contained
in the random data section, the R2 may incorrectly recognize that data as the reception head frame
or reception end frame.
(3) The length of the statement that can be received with frame reception must be shorter than the
reception data storage area size.
If the length of the statement to be received exceeds the size of the reception data storage area,
"reception data size over error (BBA2
If the length of the statement to be received exceeds the size of the reception data storage area,
"reception data size over error (BBA2
H
)" will occur.
If the reception head frame/reception end frame abort designation (
R 2
110
H
) is set to "Do not abort
(0)", the reception head frame/end frame size will be contained in the reception data size when the
process is completed.
In this case, the reception data size when reading of the reception data to the programmable
controller CPU is requested will be as follows.
process is completed.
In this case, the reception data size when reading of the reception data to the programmable
controller CPU is requested will be as follows.
Reception data size
= Reception end data size + (data size of the received frame data)
= Reception end data size + (data size of the received frame data)
Thus, the reception end data size designation and reception data size will not match.