W5200 datasheet(63/88 Pages) WIZNET

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Sn_DHAR4 = 0x01;

Sn_DHAR5 = 0x0B;

Sn_DIPR0 = 211;

/* set Multicast-Group IP address(211.1.1.11) */

Sn_DIPR1 = 1;

Sn_DIPR2 = 1;

Sn_DIRP3 = 11;

Sn_DPORT0 = 0x0BB8; /* set Multicast-GroupPort number(3000) */

Sn_PORT0 = 0x0BB8;

/* set SourcePort number(3000) */

Sn_MR = 0x02 | 0x80; /* set UDP mode & Multicast on Socket n Mode Register */

Sn_CR = OPEN;

/* set OPEN command */

/* wait until Sn_SR is changed to SOCK_UDP */

if (Sn_SR != SOCK_UDP) Sn_CR = CLOSE; goto START;

}

Check received data

Refer to the “5.2.2.1 Unicast & Broadcast.”

Receiving process

Refer to the “5.2.2.1 Unicast & Broadcast.”

Check send data / Sending Process

Since the user sets the information about multicast-group at SOCKET initialization, user

does not need to set IP address and port number for destination any more. Therefore,

copy the transmission data to internal TX memory and executes SEND command.

{

/* first, get the free TX memory size */

FREESIZE:

freesize = Sn_TX_FSR;

if (freesize<len) goto FREESIZE;

// len is send size

/* calculate offset address */

dst_mask = Sn_TX_WR0 &gSn_TX_MASK;

// dst_mask is offset address

/* calculate start address(physical address) */

dst_ptr = gSn_TX_BASE + dst_mask;

// dst_ptr is physical start address

/* if overflow SOCKETTX memory */

if ( (dst_mask + len) > (gSn_TX_MASK + 1) )

{

W5200 Datasheet(PDF) 63 Page - WIZnet Co., Ltd