6 F 3 B 0 3 6 2

Message transmission UDP port number

As described in chapter 1, UDP/IP is used for both computer link and PC link protocol transmission, which are collectively referred to as message transmission. These techniques use dedicated UDP sockets that are separate from those used by socket interface transmission.

Set the port number to a value in the range 1024 to 65535. (UNIX allocates port numbers 1 to 1023 for standard services.)

The UDP port number specified at A+4 is the UDP port number allocated for message transmission (receive). The two port numbers following that port number are automatically allocated for message transmission (send). If computer link protocol/PC link protocol reception is performed directed at the message transmission UDP port number specified at A+4, the Ethernet Port/T2N will process the received data in the order received and send the result from one of the message transmission send ports. (See figure 4.5.)

Ethernet Port

Message transmission receive port (port number 2000)

Message transmission send port 1 (port number 2001)

Message transmission send port 2 (port number 2002)

Computer link/

PC link protocol transmission

Computer link protocol transmission

PC link protocol transmission

Figure 4.5 Relationship between Message Transmission Send and Receive Port Numbers

As mentioned in the section on socket interface transmission, UDP port numbers used for message transmission must not duplicate UDP socket port numbers or TCP socket port numbers.

c.Status (See figure 4.3 for details on bits C, D, E and F.)

B B+1

F E D C B A 9 8 7 6 5 4 3 2 1 0

 

 

 

 

0

0

0

0

TermSTS

Detailed information (Only valid when TermSTS = 0BH.)

d.Important items

An error will occur if the Ethernet Port is in run mode or down mode.

Run mode - Status: Transmission error (TermSTS = 0BH)

Detailed information: Port mode error (0040H)

Down mode - Status: Module error (TermSTS = 06H)

An error occurs if a UDP port number is set to a value outside the range 1024 to 65535.

Status: Transmission error (TermSTS = 0BH)

Detailed information: Port number error (0071H)

e.Sample program

This sample ladder program issues a parameter setup request to the channel 1 Ethernet Port.

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Toshiba T2N instruction manual ∙ Message transmission UDP port number