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IM9000F02-E2
5. LADDER COMMUNICATION
5.1 Communication protocol
Ladder communication is a communication means provided for connecting with the PLC. The
REX-F9000 uses the ignored process for the ladder communication protocol.
z
Definition of protocol
Read
:
Based on a data request from the PLC, data is sent to the PLC from the REX-F9000.
Write
: Based on a data request from the PLC, data is received by the REX-F9000.
5.1.1 Communication data configuration
PLC
o
REX-F9000 (During data send from PLC)
c
d
e
f
g
h
i
Number of bytes
1
1
2
2
2
1
1
Number of BCD
digits
2
2
4
4
4
2
2
Details
STX
(02H)
ADR
ID
CMD
DAT
CR
(0DH)
LF
(0AH)
REX-F9000
o
PLC (During data receive by PLC)
c
d
e
f
g
f
g
h
i
Number of
bytes
1
1
2
2
2
2
2
1
1
Number of
BCD digits
2
2
4
4
4
4
4
2
2
Details
STX
(02H)
ADR
ID
CMD
DAT
CMD
DAT
CR
(0DH)
LF
(0AH)
c
STX
This is the transmission control character which indicates the start of the text (identifier and
data). Set to STX (02H) fixed.
d
ADR [Device address]
This data corresponds to the device address to select one REX-F9000 from among many
REX-F9000s to which the PLC is multi-drop-connected. This should be the same as the
device address set value in "
3.4 Device address setting
" (P.9).
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