Operation Of Control Line - Mitsubishi Electric FX3U-232-BD User Manual

FX Series PLC User's Manual - Data Communication Edition
Non-Protocol Communication (RS/RS2 Instruction)
6.3

Operation of Control Line

6.3.1 FX (before Ver. 2.00), FX
2N
FX PLCs before Ver. 2.00, and FX
2N
bidirectional communication.
When the sending flag is set to ON during receiving, the sending wait flag M8121 turns ON. When the
receiving complete flag turns ON from OFF, the PLC starts to send.
1. When the control line is not provided
RS
instruction
OFF ON
driving
SD (TXD)
Send data
Sending
request
M8122
Sending wait
flag
M8121
RD (RXD)
Receive data
Receiving
complete
M8123
*1. Set it to 2 scan times or more in FX
2. When the control line is in the standard mode
Use this mode when only sending or receiving.
1) When only sending is executed
RS
instruction
driving
SD (TXD)
Send data
Sending
request
M8122
ER (DTR)
DR (DSR)
F-52
(FX), FX
2
(FX), FX
2
Message
1
ON OFF
100 s or more
Receiving wait status
is started.
OFF ON
Message
1
OFF ON
OFF
OFF ON
, FX , FX , FX
2C 0N 1S
, FX , FX , FX
2C 0N 1S
OFF
*1
Message Message
2
OFF ON
Reset it in a sequence program.
While it remains ON, the PLC cannot receive the next set of data.
(FX), FX , FX , FX
2 2C 0N 1S
Message
1
ON
6 Creating Programs (RS Instruction)
6.3 Operation of Control Line
and FX PLCs
1N 1NC
, FX PLCs execute half-duplex,
1N 1NC
Message
3
ON
3
ON
, FX and FX PLCs.
1N 1NC
Message
2