W5100 datasheet(33/72 Pages) WIZNET

33 / 72 page

Sn_DIPR (Socket n Destination IP Address Register) [R/W] [0x040C–0x040F, 0x050C–0x050F,

0x060C–0x060F, 0x070C–0x070F] [0x00]

This register sets the Destination IP Address of each Socket to be used in setting the TCP

connection.

In active mode, IP address needs to be set before executing the Connect

command. In passive mode, W5100 sets up the connection and then is internally updated

with peer IP.

In UDP mode, this register value decided to user’s written value after receiving peer’s ARP

response. Before receiving peer’s ARP response, this register has reset value.

Ex) In case of Socket 0 Destination IP address = 192.168.0.11, configure as below.

0x040C

0x040D

0x040E

0x040F

192 (0xC0)

168 (0xA8)

0 (0x00)

11 (0x0B)

Sn_DPORT (Socket n Destination Port Register) [R/W] [0x0410–0x0411, 0x0510–0x0511,

0x0610–0x0611, 0x0710–0x0711] [0x00]

This register sets the Destination Port number of each socket to be used in setting the TCP

connection. In active mode, port number needs to be set before executing the Connect

command. In passive mode, W5100 sets up the connection and then is internally updated

with peer port number.

In UDP mode, this register value decided to user’s written value after receiving peer’s ARP

response. Before receiving peer’s ARP response, this register has reset value.

Ex) In case of Socket 0 Destination Port = 5000(0x1388), configure as below,

0x0410

0x0411

0x13

0x88

Sn_MSS (Socket n Maximum Segment Size Register) [R/W] [0x0412-0x0413, 0x0512-

0x0513, 0x0612-0x0613, 0x0712-0x0713] [0x 0000]

This register is used for MSS (Maximum Segment Size) of TCP, and the register displays MSS set

by the other party when TCP is activated in Passive Mode.

Ex) In case of Socket 0 MSS = 1460(0x05B4), configure as below,

0x0412

0x0413

0x05

0xB4

W5100 Datasheet(PDF) 33 Page - WIZnet Co., Ltd