Mitsubishi MELSEC LJ71C24, Руководство пользователя

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9 DATA COMMUNICATION USING THE PREDEFINED PROTOCOL
Item Description Remark
Data Flow Byte swap (by word)
When sending: Sends a calculated check code
swapping the upper byte and
lower byte by word.
When receiving: Manipulates receive data as a
check code swapping the
upper byte and lower byte by
word.
Effective only if the data length
is 4 bytes.
Not settable when
"Processing Method"
is "16-bit CRC (for
MODBUS)" or when
the "Data Length" is
set to "1 (byte)".
Complement
Calculation Select the complement calculation.
No complement calculation/One's complement/Two's complement
Not settable when
"Processing Method"
is "16-bit CRC (for
MODBUS)"
Start
Select the starting element number of the calculating range.
The range is 1 to 32.
Calculating
Range
End
Select the ending element number of the calculating range.
The range is 1 to 32.
-
POINT
y When "Code Type" is "ASCII Hexadecimal", an ASCII BIN conversion error
(7F20
H
) may occur if a string except for '0'-'9' 'A'-'F' 'a'-'f' is received.
y When "Code Type" is "ASCII Decimal", an ASCII BIN conversion error (7F20
H
)
may occur if a string except for '0'-'9' is received.
y Only one Check code can be placed in a packet.
y Packet elements placed behind a Check code cannot be included in the
calculating range.
y A Check code cannot be included in the calculated range.
y When a calculated check code (Sum check/Horizontal parity/16-bit CRC) does
not match a received check code, a sum check error (7F24
H
) may occur.
y One or more elements are required before a Check code.