Mitsubishi FX3U-ENET, Руководство пользователя

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MELSEC-F
10 USING THE E-MAIL FUNCTION
10
(2) Data conversion method used by the Ethernet module
The following shows the data conversion method used by the Ethernet module.
When sending e-mails When receiving e-mails
PLC
Subject
(ASCII data)
Main text
(ASCII data)
Attached file
(binary data)
(Binary data)
(ASCII data)
(CSV data)
(Does not decode)
Encode
(Base64)
Cannot be
received
Mail
server
Mail
server
Attached file
(binary data)
Subject
(ASCII data)
Main text
(ASCII data)
Decode
(Base64/7bit)
Encode
(7bit)
Encode
(Base64/7bit)
PLC
Operation for sending e-mails
(FROM/T
O instruction)
Instruction for receiving e-mails
(FROM/T
O instruction)
(3) Flow of the e-mail
The following diagram illustrates the flow of e-mail sent by the PLC to the external
device:
PLC
Mail send
Ethernet
module
Mail server
PC
1) 2)
5)
Checks whether or not any mails
were received
Stores receive mail
3)
4)
Confirms
information of
receive mail
Stores information
receive mail
Request to receive mail
No mail
received
Mails received
Mail server
PLC
Ethernet
module
FROM/TO
instruction
(Mail send)
FROM/TO
instruction
(Reads receive
mail)
1) Send an e-mail to the mail server of the local station's Ethernet module.
2) The mail server of the local station's Ethernet module sends the e-mail to the
receive mail server of the send destination device.
[When receiving by the Ethernet module]
3) The Ethernet module confirms mail receiving to be active or not for the time
set in the parameters, and stores the results in the buffer memory.
4) By executing the mail receiving command issued by the FROM/TO
instruction, the Ethernet module reads e-mails from the e-mail server to the
mail buffer memory.
When receiving e-mails, the Ethernet module reads the number of
remaining receive mails on the mail server and stores this number in the
buffer memory.
[When receiving by a PC]
5) Mails can be received using applications such as e-mail software.