5.9.1 Execution

main.c - Initialize the device and connect to a server using SSL.

Code summary.

Configure the network and server parameters in main.h.

/** Wi-Fi Settings */
#define MAIN_WLAN_SSID                  "DEMO_AP" /**< Destination SSID */
#define MAIN_WLAN_AUTH                  M2M_WIFI_SEC_WPA_PSK /**< Security type */
#define MAIN_WLAN_PSK                   "12345678" /**< Password for Destination SSID */

/** All SSL defines */
#define MAIN_HOST_NAME                  "www.google.com"
#define MAIN_HOST_PORT                  443

Initialize the socket module and create the UDP server socket.
```
socketInit();
registerSocketCallback(socket_cb, resolve_cb);
```

Connect to the AP.

/* Connect to router. */
m2m_wifi_connect((char *)MAIN_WLAN_SSID, sizeof(MAIN_WLAN_SSID),
        MAIN_WLAN_AUTH, (char *)MAIN_WLAN_PSK, M2M_WIFI_CH_ALL);

After the device is connected to the AP, the gethostbyname() function will be executed.

static void wifi_cb(uint8_t u8MsgType, void *pvMsg)
{
    case M2M_WIFI_REQ_DHCP_CONF:
    {
        /* Obtain the IP Address by network name */
        gethostbyname((uint8_t *)MAIN_HOST_NAME);

In the main loop, try to connect to the SSL server after resolving the domain host name.
```
if (sslConnect() != SOCK_ERR_NO_ERROR) {
    gu8SocketStatus = SocketInit;
}
```

If successfully connected, the socket_cb() function will be called with the SOCKET_MSG_CONNECT message.

static void socket_cb(SOCKET sock, uint8_t u8Msg, void *pvMsg)
{
    switch (u8Msg) {
    case SOCKET_MSG_CONNECT:
        if (pstrConnect && pstrConnect->s8Error >= SOCK_ERR_NO_ERROR)
            printf("Successfully connected.\r\n");
    break;

You can receive data in the socket_cb() function with the SOCKET_MSG_RECVFROM message when a client device sends data. (Use the “UDP Client” example.)

static void socket_cb(SOCKET sock, uint8_t u8Msg, void *pvMsg)
{
    ...
    } else if (u8Msg == SOCKET_MSG_RECVFROM) {
    tstrSocketRecvMsg *pstrRx = (tstrSocketRecvMsg *)pvMsg;
    if (pstrRx->pu8Buffer && pstrRx->s16BufferSize) {
        printf("socket_cb: received app message.(%u)\r\n", packetCnt);
	/* Prepare next buffer reception. */
	recvfrom(sock, gau8SocketTestBuffer, MAIN_WIFI_M2M_BUFFER_SIZE, 0);

Build the program and download it into the board.
Start the application.

Note: To set up an SSL connection, a root certificate must be installed.

AN5305

5.9.1 Execution