Enable Wi-Fi network

.gitignore

+compile_commands.json
\ No newline at end of file

main.cpp

 #include "mbed.h"
+#include "mbed_trace.h"
+#include "NTPClient.h"
+
+#define TRACE_GROUP  "Main"
+
+
+NetworkInterface* network = NULL;
+
+
+NetworkInterface* connect_network() {
+    NetworkInterface* net = NULL;
+
+    tr_info("Opening network interface...");
+
+    net = NetworkInterface::get_default_instance();
+    if (!net) {
+        tr_error("Unable to open network interface.");
+        return NULL;
+    }
+
+    nsapi_error_t net_status = NSAPI_ERROR_NO_CONNECTION;
+    while ((net_status = net->connect()) != NSAPI_ERROR_OK) {
+        tr_error("Unable to connect to network (%d). Retrying...", net_status);
+    }
+    SocketAddress address;
+    net->get_ip_address(&address);
+    tr_info("Connected to the network successfully. IP address: %s\n", address.get_ip_address());
+
+    return net;
+}
+
+int sync_rtc_time(NetworkInterface* net, const char* ntp_server = NULL) {
+    const char* ntp_srv = NULL;
+
+    if (net == NULL) {
+        return -1;
+    }
+
+    if (ntp_server) {
+        ntp_srv = ntp_server;
+    } else {
+        ntp_srv = "ntp.aliyun.com";
+    }
+    NTPClient ntp(net);
+    ntp.set_server(ntp_srv, 123);
+    tr_info("Try to get timestamp from %s", ntp_srv);
+    time_t now = ntp.get_timestamp();
+    if (now <= 0) {
+        tr_error("Failed to retrieve the time from %s:123", ntp_srv);
+        return -1;
+    }
+    set_time(now);
+    tr_info("Time is now %s", ctime(&now));
+
+    return 0;
+}
 
 int main() {
+    int ret = 0;
+
+    mbed_trace_init();
+
+    #ifdef MBED_MAJOR_VERSION
+        printf("Mbed OS version %d.%d.%d\n\n", MBED_MAJOR_VERSION, MBED_MINOR_VERSION, MBED_PATCH_VERSION);
+    #endif
+
+  // Connect to network
+    network = connect_network();
+    if (network == NULL) {
+        return -1;
+    }
+
+    // sync the real time clock (RTC)
+    ret = sync_rtc_time(network);
+    if (ret != 0) {
+        return ret;
+    }
+
     return 0;
 }
\ No newline at end of file

mbed_app.json

 {
+    "macros": [
+    ],
     "target_overrides": {
-        "K64F": {
-            "platform.stdio-baud-rate": 9600
+        "*": {
+            "nsapi.default-wifi-security": "WPA_WPA2",
+            "nsapi.default-wifi-ssid": "\"NETGEAR86\"",
+            "nsapi.default-wifi-password": "\"raspberry\"",
+            "mbed-trace.enable": 1,
+            "mbed-trace.max-level": "TRACE_LEVEL_DEBUG",
+            "platform.stdio-baud-rate": 115200,
+            "platform.stdio-convert-newlines": true
+
+        },
+        "B_L4S5I_IOT01A": {
+            "target.network-default-interface-type": "WIFI",
+            "nsapi.default-wifi-security": "WPA_WPA2",
+            "ism43362.provide-default": true,
+            "ism43362.wifi-country-code": "\"CN\""
+        },
+        "DISCO_L475VG_IOT01A": {
+            "target.network-default-interface-type": "WIFI",
+            "nsapi.default-wifi-security": "WPA_WPA2",
+            "ism43362.provide-default": true,
+            "ism43362.wifi-country-code": "\"CN\""
         }
     }
 }
\ No newline at end of file

ntp-client.lib

+https://github.com/ARMmbed/ntp-client/#a4ccf62992b9adc5086a9afea08fa4deb2e2fbd7

wifi-ism43362.lib

+https://github.com/ARMmbed/wifi-ism43362/#8b5bda2b2724ca08ce1a44961a82b3d6f7c59706