Active Open Procedure - Mitsubishi Electric QJ71E71-100 User Manual

7.2.3

Active open procedure

Active open is a connection method that performs an active open process on a connected device in Passive open wait
status. The procedure that the E71 performs an Active open process is as follows. For the OPEN/CLOSE instructions,
refer to "DEDICATED INSTRUCTIONS". (
Open/close processes for the connection number 1
Ex.
Open status
Open enable status
(closed)
Closed status
Initial normal completion
signal X19
OPEN instruction
OPEN instruction
completion device
OPEN instruction
completion device + 1
Open abnormal detection
signal X18
CLOSE instruction
CLOSE instruction
completion device
CLOSE instruction
completion device + 1
Open completion signal
(address: 5000
Open request signal
(address: 5002
90
Parameter communications
Power-on completed
)
H
)
H
Page 235, CHAPTER 15)
1
2
Abnormally ended
ACK
SYN
3
SYN + ACK
4
1 scan
Abnormally ended
5
FIN
7
6
FIN + ACK
1 scan
Abnormally
ended
ACK