File content as of revision 2:7b8ab39a1b6d:

#include "mbed.h"
#include "GUI.h"
#include "mbed_events.h"
#include "ntp-client/NTPClient.h"
Thread netTimeThreadHandle;
WiFiInterface *wifi;
#define MBED_CONF_APP_WIFI_SSID "brackenhillc"
#define MBED_CONF_APP_WIFI_PASSWORD "1broches"
EventQueue *displayQueue;
Semaphore WiFiSemaphore;
/******************************************************************************************
*
* Display Functions
*
********************************************************************************************/
#define DISP_LEFTMARGIN 10
#define DISP_TOPMARGIN 4
#define DISP_LINESPACE 2
// updateDisplayWiFiStatus
// Used to display the wifi status
void updateDisplayWiFiStatus(char *status)
{
    GUI_SetFont(GUI_FONT_16_1);
    GUI_DispStringAt(status,DISP_LEFTMARGIN, DISP_TOPMARGIN);
    free(status);
}
// updateDisplayWiFiConnectAttempts
// This function displays the number of attempted connections
void updateDisplayWiFiConnectAttempts(int count)
{
    char buffer[128];
    snprintf(buffer,sizeof(buffer),"WiFi Connect Attempts = %d",count);
    GUI_SetFont(GUI_FONT_16_1);
    GUI_DispStringAt(buffer,DISP_LEFTMARGIN, DISP_TOPMARGIN + (GUI_GetFontSizeY()+DISP_LINESPACE) );
}
// updateDisplayNTPFailed
// updates the display with the number of time the NTP Server has been called
// and got a failed response
void updateDisplayNTPFailed(void)
{
    static int count=0;
    char buffer[128];
    count = count + 1;
    snprintf(buffer,sizeof(buffer),"NTP Update Failure = %d\n",count);
    GUI_SetFont(GUI_FONT_16_1);
    GUI_DispStringHCenterAt(buffer,LCD_GetXSize()/2,LCD_GetYSize() - 2*GUI_GetFontSizeY()); // near the bottom
}
// updateDisplayNTPCount
// updates the display with the number of time the NTP Server has been called
void updateDisplayNTPCount(void)
{
    static int count=0;
    char buffer[128];
    count = count + 1;
    snprintf(buffer,sizeof(buffer),"NTP Updates = %d\n",count);
    GUI_SetFont(GUI_FONT_16_1);
    GUI_DispStringHCenterAt(buffer,LCD_GetXSize()/2,LCD_GetYSize() - GUI_GetFontSizeY()); // near the bottom
}
// updateDisplayTime
// This function updates the time on the screen
void updateDisplayTime()
{
    time_t rawtime;
    struct tm * timeinfo;
    char buffer [128];
    time (&rawtime);
    //rawtime = rawtime - (4*60*60); // UTC - 4hours ... serious hack which only works in summer
    rawtime = rawtime + 3600;  // GMT + 1 for BST
    timeinfo = localtime (&rawtime);
    strftime (buffer,sizeof(buffer)," %r ",timeinfo);
    GUI_SetFont(GUI_FONT_32B_1);
    GUI_DispStringHCenterAt(buffer,LCD_GetXSize()/2,LCD_GetYSize()/2 - GUI_GetFontSizeY()/2 - 20);
    strftime (buffer,sizeof(buffer),"   %A   ",timeinfo);
    GUI_SetFont(GUI_FONT_32B_1);
    GUI_DispStringHCenterAt(buffer,LCD_GetXSize()/2,LCD_GetYSize()/2 - GUI_GetFontSizeY()/2 + 20);
    strftime (buffer,sizeof(buffer)," %D ",timeinfo);
    GUI_SetFont(GUI_FONT_32B_1);
    GUI_DispStringHCenterAt(buffer,LCD_GetXSize()/2,LCD_GetYSize()/2 - GUI_GetFontSizeY()/2 + 60);
}
/******************************************************************************************
* NTPTimeThread
* This thread calls the NTP Timeserver to get the UTC time
* It then updates the time in the RTC
* And it updates the display by adding an event to the display queue
********************************************************************************************/
void NTPTimeThread()
{
    static time_t old_timestamp = 0, timestamp;
    NTPClient ntpclient(wifi);
    while(1) {
        if(wifi->get_connection_status() == NSAPI_STATUS_GLOBAL_UP) {
            timestamp = ntpclient.get_timestamp();
            if (timestamp < old_timestamp) {
                displayQueue->call(updateDisplayNTPFailed);
            } else {
                set_time(timestamp);
                displayQueue->call(updateDisplayNTPCount);
            }
        }
        old_timestamp = timestamp;
        ThisThread::sleep_for(300000); // Goto the NTP server every 5 minutes
    }
}
/******************************************************************************************
*
* Main & WiFi Thread
*
********************************************************************************************/
// wifiStatusCallback
// Changes the display when the wifi status is changed
void wifiStatusCallback(nsapi_event_t status, intptr_t param)
{
    const int buffSize=40;
    char *statusText;
    statusText = (char *)malloc(buffSize);
    switch(param) {
        case NSAPI_STATUS_LOCAL_UP:
            snprintf(statusText,buffSize,"WiFi IP = %s",wifi->get_ip_address());
            break;
        case NSAPI_STATUS_GLOBAL_UP:
            snprintf(statusText,buffSize,"WiFi IP = %s",wifi->get_ip_address());
            break;
        case NSAPI_STATUS_DISCONNECTED:
            WiFiSemaphore.release();
            snprintf(statusText,buffSize,"WiFi Disconnected");
            break;
        case NSAPI_STATUS_CONNECTING:
            snprintf(statusText,buffSize,"WiFi Connecting");
            break;
        default:
            snprintf(statusText,buffSize,"Not Supported");
            break;
    }
    displayQueue->call(updateDisplayWiFiStatus,statusText);
}
int main()
{
    int wifiConnectionAttempts;
    int ret;
    GUI_Init();
    displayQueue = mbed_event_queue();
    displayQueue->call_every(1000, &updateDisplayTime);
    wifi = WiFiInterface::get_default_instance();
    wifi->attach(&wifiStatusCallback);
    while(1) {
        wifiConnectionAttempts = 1;
        do {
            ret = wifi->connect(MBED_CONF_APP_WIFI_SSID, MBED_CONF_APP_WIFI_PASSWORD, NSAPI_SECURITY_WPA_WPA2);
            displayQueue->call(updateDisplayWiFiConnectAttempts,wifiConnectionAttempts);
            if (ret != 0) {
                wifiConnectionAttempts += 1;
                ThisThread::sleep_for(2000); // If for some reason it doesnt work wait 2s and try again
            }
        } while(ret !=0);
// If the NTPThread is not running... then start it up
        if(netTimeThreadHandle.get_state() == Thread::Deleted)
            netTimeThreadHandle.start(NTPTimeThread);
        WiFiSemaphore.acquire();
    }
}