Fx 2N , Fx 2Nc; Fx , Fx 2Nc (V 2.00 Or Later) - Mitsubishi Electric MELSEC FX Series User Manual

FX communication
9.2.2 FX , FX
2N 2NC
In the FX V 2.00 or later, full duplex communication is performed. When performing half duplex
2N
communication, pay rigid attention so that the send flag is not turned on while data is received. If
it is turned on, send is started. As the result, the counterpart equipment may not be able to
receive data or the send/receive data may be damaged.
In full duplex communication, the send wait flag M8121 is not turned on.
In version V 2.00 or later, the programming protocol (Section 12) is supported while an RS
instruction remains OFF.
1 ) Do not use hardware hand shake
RS instruction
driving
Send data
SD (TXD)
Send request
M8122
Receive data
RD (RXD)
Receive
completion
M8123
2 ) Use terminal mode of control line
This mode is available for send only or receive only.
The control line and the transmission sequence are equivalent to those in the FX
whose version is earlier than V 2.00. Refer to paragraph 9.2.1.
(V 2.00 or later)
OFF ON
Data 1
OFF ON
Data 2
OFF
The receive wait
status is started
Data 3 Data 5
Data 4
ON
Reset using a program.
When it is not trurned off, the next
data cannot be received.
RS instruction 9
ON
series
2N
9-10