Use this interface to connect to and interact with the WNC M14A2A LTE Cellular Data Module which is provided by Wistron NeWeb Corporation (WNC) when using ARMmbed v5. The interface provides a Networking interface that can be used with the AT&T Cellular IoT Starter Kit that is sold by Avnet (http://cloudconnectkits.org/product/att-cellular-iot-starter-kit).

Dependencies:   WncControllerK64F

Dependents:   easy-connect-wnc easy-connect easy-connect111

Use this interface to connect to and interact with the WNC M14A2A LTE Cellular Data Module which is provided by Wistron NeWeb Corporation (WNC) when using ARMmbed v5. The interface provides a Networking interface that can be used with the AT&T Cellular IoT Starter Kit that is sold by Avnet (http://cloudconnectkits.org/product/att-cellular-iot-starter-kit).

To demonstrate the use of the Interface, a series of example programs have been provided. Links to these examples are provided below. All examples can be compiled using both the on-line compiler and the ARMmbed CLI (command line interface, see https://github.com/ARMmbed/mbed-cli)

NOTE: This library/class is specific to the AT&T Cellular IoT Starter Kit which uses a FRDM-K64F. The users mbed.org compiler should be configured to use the FRDM-K64F platform.

Example Programs

Import the example programs below and follow the README.md in each to run the example program.

  • several examples of the interface using easy_connect.
  • SMS demonstration program that demonstrates SMS usage
  • Sockets demonstration program demonstrating using TCP sockets to interact with others
  • As new example program are developed, this README will be updated

WNC FIRMWARE VERSION

The WNC14A2AInterface class currently supports the following version(s):

  • MPSS: M14A2A_v11.21.162331 APSS: M14A2A_v11.27.162331

License

This library is released under the Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License and may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

WNC14A2AInterface.cpp

Committer:
JMF
Date:
2017-04-21
Revision:
8:1c11661da488
Parent:
7:9340bc9e8d64

File content as of revision 8:1c11661da488:


#include "WNC14A2AInterface.h"
#include <Thread.h>
#include <string> 

/** WNC14A2AInterface class
 *  Implementation of the NetworkInterface for the AT&T IoT Starter Kit 
 *  based on the WNC 14A2A LTE Data Module
 */

#define WNC14A2A_MISC_TIMEOUT 3000
#define WNC14A2A_RESTART_TIMEOUT 10000
#define WNC14A2A_COMMUNICATION_TIMEOUT 100
#define READ_EVERYMS    500

/////////////////////////////////////////////////////
// NXP GPIO Pins that are used to initialize the WNC Shield
/////////////////////////////////////////////////////
DigitalOut  mdm_uart2_rx_boot_mode_sel(PTC17);  // on powerup, 0 = boot mode, 1 = normal boot
DigitalOut  mdm_power_on(PTB9);                 // 0 = modem on, 1 = modem off (hold high for >5 seconds to cycle modem)
DigitalOut  mdm_wakeup_in(PTC2);                // 0 = let modem sleep, 1 = keep modem awake -- Note: pulled high on shield
DigitalOut  mdm_reset(PTC12);                   // active high
DigitalOut  shield_3v3_1v8_sig_trans_ena(PTC4); // 0 = disabled (all signals high impedence, 1 = translation active
DigitalOut  mdm_uart1_cts(PTD0);

// Define pin associations for the controller class to use be careful to 
//  keep the order of the pins in the initialization list.

using namespace WncControllerK64F_fk;       // namespace for the controller class use

WncGpioPinListK64F wncPinList = { 
    &mdm_uart2_rx_boot_mode_sel,
    &mdm_power_on,
    &mdm_wakeup_in,
    &mdm_reset,
    &shield_3v3_1v8_sig_trans_ena,
    &mdm_uart1_cts
};

Thread smsThread;
static Mutex _pwnc_mutex;

static WNCSOCKET _sockets[WNC14A2A_SOCKET_COUNT];
BufferedSerial mdmUart(PTD3,PTD2,1024,1);       //UART for WNC Module

//-------------------------------------------------------------------------
//
// Class constructor.  May be invoked with or without the APN and/or pointer
// to a debug output.  After the constructor has completed, the user can 
// check _errors to determine if any errors occured during instanciation.
// _errors = 0 when no errors occured
//           1 when power-on error occured
//           2 when settng the APN error occured
//           4 when unable to get the network configuration
//           8 when allocating a new WncControllerK64F object failed
//          NSAPI_ERROR_UNSUPPORTED when attempting to create a second object
//

WNC14A2AInterface::WNC14A2AInterface(WNCDebug *dbg) : 
 m_wncpoweredup(0),
 _pwnc(NULL),
 m_active_socket(-1),
 m_smsmoning(0)
{
    _errors = NSAPI_ERROR_OK;
    
    m_debug=false;

    if( _pwnc ) { //can only have a single instance of class
        _errors =  NSAPI_ERROR_UNSUPPORTED;
        return;
        }
    for( int i=0; i<WNC14A2A_SOCKET_COUNT; i++ ) {
        _sockets[i].socket = i;
        _sockets[i].addr = NULL;
        _sockets[i].opened=false;
        _sockets[i].proto=NSAPI_TCP;
        }

    
    memset(_mac_address,0x00,sizeof(_mac_address));

    _debugUart = dbg;
    if( dbg != NULL ) {
        dbg->printf("Adding DEBUG output\n");
        _pwnc = new WncControllerK64F(&wncPinList, &mdmUart, dbg);
        m_debug=true;
        if( _pwnc ) 
            _pwnc->enableDebug(1,1);
        }
    else 
        _pwnc = new WncControllerK64F_fk::WncControllerK64F(&wncPinList, &mdmUart, NULL);
        
    if( !_pwnc ) {
        debugOutput(_debugUart,(char*)", FAILED!\n");
        _errors = NSAPI_ERROR_DEVICE_ERROR;
        }
    else
        debugOutput(_debugUart, (char*)"\n");
}

/*-------------------------------------------------------------------------
 * standard destructor... free up allocated memory
 */

WNC14A2AInterface::~WNC14A2AInterface()
{
    delete _pwnc;  //free the existing WncControllerK64F object
}

nsapi_error_t WNC14A2AInterface::connect() 
{
    debugOutput(_debugUart,(char*)"+CALLED connect(void)\n");
    return connect(NULL,NULL,NULL);
}

/*-------------------------------------------------------------------------
 * This call powers up the WNC module and connects to the user specified APN.  If no APN is provided
 * a default one of 'm2m.com.attz' will be used (the NA APN)
 *
 * Input: *apn is the APN string to use
 *        *username - NOT CURRENTLY USED
 *        *password - NOT CURRENTLY USED
 *
 * Output: none
 *
 * Return: nsapi_error_t
 */
nsapi_error_t WNC14A2AInterface::connect(const char *apn, const char *username, const char *password) 
{
    debugOutput(_debugUart,(char*)"+ENTER connect(apn,user,pass)\n");
    if( !_pwnc )
        return (_errors=NSAPI_ERROR_NO_CONNECTION);

    if (!apn)
        apn = "m2m.com.attz";

    if (!m_wncpoweredup) {
        debugOutput(_debugUart,(char*)"+call powerWncOn using '%s'\n",apn);
        _pwnc_mutex.lock();
        m_wncpoweredup=_pwnc->powerWncOn(apn,40);
        _pwnc_mutex.unlock();
        _errors = m_wncpoweredup? 1:0;
        }
    else { //we've already called powerWncOn and set the APN, so just set the APN 
        debugOutput(_debugUart,(char*)"+already powered on, set APN to: %s\n",apn);
        _pwnc_mutex.lock();
        _errors = _pwnc->setApnName(apn)? 1:0;
        _pwnc_mutex.unlock();
        }

    _pwnc_mutex.lock();
    _errors |= _pwnc->getWncNetworkingStats(&myNetStats)? 2:0;
    _pwnc_mutex.unlock();

    debugOutput(_debugUart,(char*)"+EXIT connect %02X\n",_errors);
    return (!_errors)? NSAPI_ERROR_NO_CONNECTION : NSAPI_ERROR_OK;
}

/*--------------------------------------------------------------------------
 * This function calls the WNC to retrieve the device (this WNC) connected IP 
 * address once we are connected to the APN.
 *
 * Inputs: NONE.
 *
 * Output: none.
 *
 * Return: pointer to the IP string or NULL 
 */
const char *WNC14A2AInterface::get_ip_address()
{
    const char *ptr=NULL; 

    _pwnc_mutex.lock();
    if ( _pwnc->getWncNetworkingStats(&myNetStats) ) {
        CHK_WNCFE(( _pwnc->getWncStatus() == FATAL_FLAG ), null);
        ptr = &myNetStats.ip[0];
    }
    _pwnc_mutex.unlock();
    _errors=NSAPI_ERROR_NO_CONNECTION;
    return ptr;
}

#if 0
/*--------------------------------------------------------------------------
 * This function calls the WNC to retrieve the currently connected IP address
 * it will be a bogus 192.168.0.1 if we are not connected to anyone
 *
 * Inputs: NONE.
 *
 * Output: none.
 *
 * Return: pointer to the IP string or NULL 
 */
const char *WNC14A2AInterface::get_ip_address()
{
    static char *ptr=NULL, ipAddrStr[25];
    debugOutput(_debugUart,(char*)"+ENTER get_ip_address()\n");

    memset(ipAddrStr, 0x00, sizeof(ipAddrStr));
    _pwnc_mutex.lock();

    if( _pwnc && m_active_socket != -1 )
        if( _pwnc->getIpAddr(m_active_socket, ipAddrStr) )
          ptr=ipAddrStr;
    _pwnc_mutex.unlock();
    _errors=NSAPI_ERROR_NO_CONNECTION;
    return ptr;
}
#endif

/* -------------------------------------------------------------------------
 * Open a socket for the WNC.  This doesn't actually open the socket within
 * the WNC, it only allocates a socket device and saves the pertinet info
 * that will be required with the WNC socket is opened. The m_active_socket
 * is also updated to this socket as it is assumed this socket should be used
 * for subsequent interactions.
 *
 * Input: 
 *  - a pointer to a handle pointer.  
 *  - The type of socket this will be, either NSAPI_UDP or NSAP_TCP
 *
 * Output: *handle is updated
 *
 * Return:
 *  - socket being used if successful, -1 on failure
 */
int WNC14A2AInterface::socket_open(void **handle, nsapi_protocol_t proto) 
{
    int i;
    debugOutput(_debugUart,(char*)"+ENTER socket_open()\n");

    // search through the available sockets (WNC can only support a max amount).
    for( i=0; i<WNC14A2A_SOCKET_COUNT; i++ )
        if( !_sockets[i].opened )
            break;

    if( i == WNC14A2A_SOCKET_COUNT ) {
        _errors=NSAPI_ERROR_NO_SOCKET;
        return -1;
        }

    m_active_socket = i;           
    _sockets[i].socket = i;        //save this index to make easier later-on
    _sockets[i].url="";
    _sockets[i].opened = true;     //ok, we are using this socket now
    _sockets[i].addr = NULL;       //but we haven't opened it yet
    _sockets[i].proto = (proto == NSAPI_UDP) ? 0 : 1; //set it up for what WNC wants
    *handle = &_sockets[i];

    debugOutput(_debugUart,(char*)"+USING Socket index %d, OPEN=%s, proto =%d\nEXIT socket_open()\n",
    i, _sockets[i].opened?"YES":"NO", _sockets[i].proto);
    
    _errors = NSAPI_ERROR_OK;
    return i;
}

/*-------------------------------------------------------------------------
 * Connect a socket to a IP/PORT.  Before you can connect a socket, you must have opened
 * it.
 *
 * Input: handle - pointer to the socket to use
 *        address- the IP/Port pair that will be used
 *
 * Output: none
 *
 * return: 0 or greater on success (value is the socket ID)
 *        -1 on failure
 */
int WNC14A2AInterface::socket_connect(void *handle, const SocketAddress &address) 
{
    WNCSOCKET *wnc = (WNCSOCKET *)handle;   

    debugOutput(_debugUart,(char*)"+ENTER socket_connect()\n");
    debugOutput(_debugUart,(char*)"+IP  = %s\n+PORT= %d\n", address.get_ip_address(), address.get_port());
    
    if (!_pwnc || m_active_socket == -1) {
        _errors = NSAPI_ERROR_NO_SOCKET;
        return -1;
        }

    if( !wnc->opened ) {
        _errors = NSAPI_ERROR_NO_SOCKET;
        return -1;
        }
    m_active_socket = wnc->socket;  //in case the user is asking for a different socket
    wnc->addr = address;
                                
    //we will always connect using the URL if possible, if no url has been provided, try the IP address
    if( wnc->url.empty() ) {
        debugOutput(_debugUart,(char*)"+call openSocketIpAddr(%d,%s,%d,%d)\n",m_active_socket, 
                           address.get_ip_address(), address.get_port(), wnc->proto);
        if( !_pwnc->openSocketIpAddr(m_active_socket, address.get_ip_address(), address.get_port(), 
                                 wnc->proto, WNC14A2A_COMMUNICATION_TIMEOUT) ) {
            _errors = NSAPI_ERROR_NO_SOCKET;
            return -1;
            }
        }
     else {
        debugOutput(_debugUart,(char*)"+call openSocketUrl(%d,%s,%d,%d)\n", m_active_socket, 
                           wnc->url.c_str(), wnc->addr.get_port(), wnc->proto);
        if( !_pwnc->openSocketUrl(m_active_socket, wnc->url.c_str(), wnc->addr.get_port(), wnc->proto) ) {
            _errors = NSAPI_ERROR_NO_SOCKET;
            return -1;
            }
        }

    debugOutput(_debugUart,(char*)"+SOCKET %d CONNECTED!\n+URL=%s\n+IP=%s; PORT=%d\n+EXIT socket_connect()\n\n",m_active_socket,
                wnc->url.c_str(), wnc->addr.get_ip_address(), wnc->addr.get_port());
    return 0;
}

/*-------------------------------------------------------------------------
 * Perform a URL name resolve, update the IP/Port pair, and nsapi_version. nsapi_version
 * could be either NSAPI_IPv4 or NSAPI_IPv6 but this functional is hard coded ti NSAPI_IPv4
 * for now. The currently active socket is used for the resolution.  
 *
 * Input: name - the URL to resolve
 *
 * Output: address - the IP/PORT pair this URL resolves to
 *         version - always assumed to be NSAPI_IPv4  currently
 *
 * Return: nsapi_error_t
 */

nsapi_error_t WNC14A2AInterface::gethostbyname(const char* name, SocketAddress *address, nsapi_version_t version)
{
    nsapi_error_t ret = NSAPI_ERROR_OK;
    char ipAddrStr[25];
    int  t_socket = 0;  //use a temporary socket place holder

    debugOutput(_debugUart,(char*)"+ENTER gethostbyname()()\n+CURRENTLY:\n");
    debugOutput(_debugUart,(char*)"+URL = %s\n+IP  = %s\n+PORT= %d\n", name, address->get_ip_address(), address->get_port());
    memset(ipAddrStr,0x00,sizeof(ipAddrStr));
    
    if (!_pwnc) 
        return (_errors = NSAPI_ERROR_NO_SOCKET);
        
    if (m_active_socket != -1)      //we might have been called before a socket was opened
        t_socket = m_active_socket; //if so, do nothing with the active socket index

    //Execute DNS query.  
    if( !_pwnc->resolveUrl(t_socket, name) )  
        return (_errors = NSAPI_ERROR_DEVICE_ERROR);

    //Now, get the IP address that the URL was resolved to
    if( !_pwnc->getIpAddr(t_socket, ipAddrStr) )
        return (_errors = NSAPI_ERROR_DEVICE_ERROR);

    address->set_ip_address(ipAddrStr);
    debugOutput(_debugUart,(char*)"+resolveUrl returned IP=%s\n",ipAddrStr);
    if( t_socket == m_active_socket ) {
        _sockets[m_active_socket].url=name;
        _sockets[m_active_socket].addr.set_ip_address(ipAddrStr);
        }

    debugOutput(_debugUart,(char*)"+EXIT gethostbyname()\n+URL = %s\n+IP  = %s\n+PORT= %d\n\n", 
                _sockets[m_active_socket].url.c_str(), address->get_ip_address(), 
                address->get_port());
    _errors = ret;
    return ret;
}
 
/*-------------------------------------------------------------------------
 * using the specified socket, send the data.
 *
 * Input: handle of the socket to use
 *        pointer to the data to send
 *        amount of data being sent
 *
 * Output: none
 *
 * Return: number of bytes that was sent
 */
int WNC14A2AInterface::socket_send(void *handle, const void *data, unsigned size) 
{
    WNCSOCKET *wnc = (WNCSOCKET *)handle;
    int r = -1;
    debugOutput(_debugUart,(char*)"+ENTER socket_send()\n");

    if (!_pwnc || m_active_socket == -1) {
        _errors = NSAPI_ERROR_NO_SOCKET;
        return 0;
        }
    else
        m_active_socket = wnc->socket; //just in case sending to a socket that wasn't last used

    debugOutput(_debugUart,(char*)"+SOCKET %d is %s, URL=%s, IP=%s, PORT=%d\n",m_active_socket,
        (char*)wnc->opened?"OPEN":"CLOSED",wnc->url.c_str(),wnc->addr.get_ip_address(),wnc->addr.get_port());
    debugOutput(_debugUart,(char*)"+WRITE [%s] (%d bytes) to socket #%d\n",data,size,wnc->socket);

    _pwnc_mutex.lock();
    if( _pwnc->write(m_active_socket, (const uint8_t*)data, size) ) 
       r = size;
    else
       debugOutput(_debugUart,(char*)"+ERROR: write to socket %d failed!\n",m_active_socket);
    _pwnc_mutex.unlock();

    debugOutput(_debugUart,(char*)"+EXIT socket_send(), successful: %d\n\n",r);
    return r;
}  

/*-------------------------------------------------------------------------
 * Called to receive data.  
 *
 * Input: handle to the socket we want to read from
 *
 * Output: data we receive is placed into the data buffer
 *         size is the size of the buffer
 *
 * Returns: The number of bytes received or -1 if an error occured
 */
int WNC14A2AInterface::socket_recv(void *handle, void *data, unsigned size) 
{
    WNCSOCKET *wnc = (WNCSOCKET *)handle;
    size_t done, cnt;
    Timer t;

    debugOutput(_debugUart,(char*)"+ENTER socket_recv(); read up to %d bytes\n",size);

    memset(data,0x00,size);  
    if (!_pwnc || m_active_socket == -1) {
        _errors = NSAPI_ERROR_NO_SOCKET;
        return -1;
        }
    else
        m_active_socket = wnc->socket; //just in case sending to a socket that wasn't last used

    t.start();
    do {
        if( !(t.read_ms() % READ_EVERYMS) )
          cnt = done = _pwnc->read(m_active_socket, (uint8_t *)data, (uint32_t) size);
        done = (cnt || (t.read_ms() > WNC14A2A_MISC_TIMEOUT))? 1:0;
        }
    while( !done );
    t.stop();
    
    if( _pwnc->getWncStatus() != WNC_GOOD ) {
        _errors = NSAPI_ERROR_DEVICE_ERROR;
        return -1;
        }

    debugOutput(_debugUart,(char*)"+EXIT socket_recv(), ret=%d\n",cnt);
    return cnt;
}

/*-------------------------------------------------------------------------
 * Close a socket 
 *
 * Input: the handle to the socket to close
 *
 * Output: none
 *
 * Return: -1 on error, otherwise 0
 */
int WNC14A2AInterface::socket_close(void *handle)
{
    WNCSOCKET *wnc = (WNCSOCKET*)handle;
    debugOutput(_debugUart,(char*)"+CALLED socket_close()\n");

    if (!_pwnc || m_active_socket == -1) {
        _errors = NSAPI_ERROR_NO_SOCKET;
        return -1;
        }
    else
        m_active_socket = wnc->socket; //just in case sending to a socket that wasn't last used
    
    if( !_pwnc->closeSocket(m_active_socket) ) {
        _errors = NSAPI_ERROR_DEVICE_ERROR;
        return -1;
        }

    wnc->opened = false;     //no longer in use
    wnc->addr = NULL;        //not open
    wnc->proto = 0;  //assume TCP for now
    _errors = NSAPI_ERROR_OK;
    return 0;
}

/*-------------------------------------------------------------------------
 * return the MAC for this device.  Because there is no MAC Ethernet 
 * address to return, this function returns a bogus MAC address created 
 * from the ICCD on the SIM that is being used.
 *
 * Input: none
 *
 * Output: none
 *
 * Return: MAC string containing "NN:NN:NN:NN:NN:NN" or NULL
 */
const char *WNC14A2AInterface::get_mac_address()
{
    string mac, str;
    debugOutput(_debugUart,(char*)"+ENTER get_mac_address()\n");

    if( _pwnc->getICCID(&str) ) {
        CHK_WNCFE((_pwnc->getWncStatus()==FATAL_FLAG), null);
        mac = str.substr(3,20);
        mac[2]=mac[5]=mac[8]=mac[11]=mac[14]=':';
        strncpy(_mac_address, mac.c_str(), mac.length());
        return _mac_address;
    }
    return NULL;
}

/*-------------------------------------------------------------------------
 * return a pointer to the current WNC14A2AInterface
 */
NetworkStack *WNC14A2AInterface::get_stack() {
    debugOutput(_debugUart,(char*)"+CALLED get_stack()\n");
    return this;
}

/*-------------------------------------------------------------------------
 * Disconnnect from the 14A2A, but we can not do that
 * so just return saying everything is ok.
 */
nsapi_error_t WNC14A2AInterface::disconnect() 
{
    debugOutput(_debugUart,(char*)"+CALLED disconnect()\n");
    return NSAPI_ERROR_OK;
}

/*-------------------------------------------------------------------------
 * allow the user to change the APN. The API takes username and password
 * but they are not used.
 *
 * Input: apn string
 *        username - not used
 *        password - not used
 *
 * Output: none
 *
 * Return: nsapi_error_t 
 */
nsapi_error_t WNC14A2AInterface::set_credentials(const char *apn, const char *username, const char *password) 
{
    debugOutput(_debugUart,(char*)"+ENTER set_credentials()\n");
    if( !_pwnc ) 
        return (_errors=NSAPI_ERROR_NO_CONNECTION);
        
    if( !apn )
        return (_errors=NSAPI_ERROR_PARAMETER);

    if( !_pwnc->setApnName(apn) )
        return (_errors=NSAPI_ERROR_DEVICE_ERROR);

    return (_errors=NSAPI_ERROR_OK);
}

/*-------------------------------------------------------------------------
 * Register a callback on state change of the socket.FROM NetworkStack
 *  @param handle       Socket handle
 *  @param callback     Function to call on state change
 *  @param data         Argument to pass to callback
 *  @note Callback may be called in an interrupt context.
 */
void WNC14A2AInterface::socket_attach(void *handle, void (*callback)(void *), void *data)
{
    debugOutput(_debugUart,(char*)"+CALLED socket_attach()\n");
}

/*-------------------------------------------------------------------------
 * check to see if we are currently regisered with the network.
 *
 * Input: none
 *
 * Output: none
 *
 * Return: ture if we are registerd, false if not or an error occured
 */
bool WNC14A2AInterface::registered()
{
    debugOutput(_debugUart,(char*)"+ENTER registered()\n");
    if( !_pwnc ) {
        _errors=NSAPI_ERROR_NO_CONNECTION;
        return false;
        }

    if ( _pwnc->getWncStatus() == WNC_GOOD ){
        _errors=NSAPI_ERROR_OK;
        return true;
        }
    _errors=NSAPI_ERROR_NO_CONNECTION;
    return false;
}

/*-------------------------------------------------------------------------
 * doDebug is just a handy way to allow a developer to set different levels
 * of debug for the WNC14A2A device.
 *
 * Input:  a Bitfield of -
 *   basic debug   = 0x01
 *   more debug    = 0x02
 *   network debug = 0x04
 *   all debug     = 0x07
 *
 * Output: none
 *
 * Returns: void
 */
void WNC14A2AInterface::doDebug( int v )
{
    if( !_pwnc )
        _errors = NSAPI_ERROR_DEVICE_ERROR;
    else
        _pwnc->enableDebug( (v&1), (v&2) );

    m_debug=(v&4);
    debugOutput(_debugUart,(char*)"+SETTING debug flag to 0x%02X\n",v);
}

/*-------------------------------------------------------------------------
 * Simple function to allow for writing debug messages.  It always 
 * checks to see if debug has been enabled or not before it
 * outputs the message.
 *
 * Input: The debug uart pointer followed by format string and vars
 *
 * Output: none
 *
 * Return: void
 */
void WNC14A2AInterface::debugOutput(WNCDebug *dbgOut, char * format, ...) 
{
    if( dbgOut && m_debug ) {
        char buffer[256];
        va_list args;
        va_start (args, format);
        vsnprintf(buffer, sizeof(buffer), format, args);
        dbgOut->puts(buffer);
        va_end (args);
        }
}


////////////////////////////////////////////////////////////////////
//  UDP methods
///////////////////////////////////////////////////////////////////

//-------------------------------------------------------------------------
//sends data to a UDP socket
int WNC14A2AInterface::socket_sendto(void *handle, const SocketAddress &address, const void *data, unsigned size)
{
    WNCSOCKET *wnc = (WNCSOCKET *)handle;
    
    debugOutput(_debugUart,(char*)"+CALLED socket_sendto()\n");
    CHK_WNCFE(( _pwnc->getWncStatus() == FATAL_FLAG ), fail);
    if (!wnc->opened) {
       int err = socket_connect(wnc, address);
       if (err < 0) 
           return err;
       }
    wnc->addr = address;

    return socket_send(wnc, data, size);
}

//receives from a UDP socket
int WNC14A2AInterface::socket_recvfrom(void *handle, SocketAddress *address, void *buffer, unsigned size)
{
    WNCSOCKET *wnc = (WNCSOCKET *)handle;
    debugOutput(_debugUart,(char*)"+CALLED socket_recvfrom()\n");
    int ret = socket_recv(wnc, (char *)buffer, size);
    if (ret >= 0 && address) 
        *address = wnc->addr;
    return ret;
}

////////////////////////////////////////////////////////////////////
//  SMS methods
///////////////////////////////////////////////////////////////////

/*-------------------------------------------------------------------------
 * IOTSMS message don't use a phone number, they use the device ICCID.  This 
 * function returns the ICCID based number that is used for this device.
 *
 * Input: none
 * Output: none
 * Return: string containing the IOTSMS number to use
 */
char* WNC14A2AInterface::getSMSnbr( void ) 
{
    char * ret=NULL;
    string iccid_str;
    static string msisdn_str;

    if( !_pwnc ) {
        _errors=NSAPI_ERROR_NO_CONNECTION;
        return NULL;
        }

    CHK_WNCFE(( _pwnc->getWncStatus() == FATAL_FLAG ), null);

    if( !_pwnc->getICCID(&iccid_str) ) 
        return ret;
 
    CHK_WNCFE(( _pwnc->getWncStatus() == FATAL_FLAG ), null);

    if( _pwnc->convertICCIDtoMSISDN(iccid_str, &msisdn_str) )
         ret = (char*)msisdn_str.c_str();    
    return ret;
}


/*-------------------------------------------------------------------------
 * Normally the user attaches his call-back function when performing
 * the listen call which enables the SMS system, but this function
 * allows them to update the callback if desired.
 *
 * input: pointer to the function to call
 * output: none
 * return: none
 */
void WNC14A2AInterface::sms_attach(void (*callback)(IOTSMS *))
{
    debugOutput(_debugUart,(char*)"+CALLED sms_attach() called\n");
    _sms_cb = callback;
}

/*-------------------------------------------------------------------------
 * Call this to start the SMS system.  It is needed to reset the WNC 
 * internal data structures related to SMS messaging
 */
void WNC14A2AInterface::sms_start(void)
{
    _pwnc_mutex.lock();                       //delete any message currently in storage
    _pwnc->deleteSMSTextFromMem('*');       //so we are notified of new incomming messages
    _pwnc_mutex.unlock();
}

/*-------------------------------------------------------------------------
 * Initialize the IoT SMS system.  Initializing it allows the user to set a 
 * polling period to check for SMS messages, and a SMS is recevied, then 
 * a user provided function is called.  
 *
 * Input: polling period in seconds. If not specified 30 seconds is used.
 *        pointer to a users calllback function
 * Output: none
 *
 * Returns: void
 */
void WNC14A2AInterface::sms_listen(uint16_t pp)
{
    debugOutput(_debugUart,(char*)"+CALLED sms_listen(%d) called\n",pp);
    if( !_pwnc ) {
        _errors=NSAPI_ERROR_NO_CONNECTION;
        return;
        }

    CHK_WNCFE(( _pwnc->getWncStatus() == FATAL_FLAG ), fail);

    if( m_smsmoning )
        m_smsmoning = false;
    if( pp < 1)
        pp = 30;


    debugOutput(_debugUart,(char*)"+setup event queue\n");
    smsThread.start(callback(&sms_queue,&EventQueue::dispatch_forever));

    _pwnc_mutex.lock();                       //delete any message currently in storage
    _pwnc->deleteSMSTextFromMem('*');       //so we are notified of new incomming messages
    _pwnc_mutex.unlock();
    sms_queue.call_every(pp*1000, mbed::Callback<void()>((WNC14A2AInterface*)this,&WNC14A2AInterface::handle_sms_event));

    m_smsmoning = true;
    debugOutput(_debugUart,(char*)"+EXIT sms_listen()\n");
}

/*-------------------------------------------------------------------------
 * process to check SMS messages that is called at the user specified period
 * 
 * input: none
 * output:none
 * return:void
 */
void WNC14A2AInterface::handle_sms_event()
{
    int msgs_available;
    debugOutput(_debugUart,(char*)"+CALLED handle_sms_event() called\n");

    if ( _sms_cb && m_smsmoning ) {
        CHK_WNCFE((_pwnc->getWncStatus()==FATAL_FLAG), fail);
        _pwnc_mutex.lock();
        msgs_available = _pwnc->readUnreadSMSText(&m_smsmsgs, true);
        _pwnc_mutex.unlock();
        if( msgs_available ) {
            debugOutput(_debugUart,(char*)"+Have %d unread texts present\n",m_smsmsgs.msgCount);
            for( int i=0; i< m_smsmsgs.msgCount; i++ ) {
                m_MsgText.number = m_smsmsgs.e[i].number;
                m_MsgText.date = m_smsmsgs.e[i].date;
                m_MsgText.time = m_smsmsgs.e[i].time;
                m_MsgText.msg = m_smsmsgs.e[i].msg;
                _sms_cb(&m_MsgText);
                }
            }
        }
    debugOutput(_debugUart,(char*)"+EXIT handle_sms_event\n");
}


/*-------------------------------------------------------------------------
 * Check for any SMS messages that are present. If there are, then  
 * fetch them and pass to the users call-back function for processing
 *
 * input: pointer to a IOTSMS message buffer array (may be more than 1 msg)
 * output:message buffer pointer is updated
 * return: the number of messages being returned
 */
int WNC14A2AInterface::getSMS(IOTSMS **pmsg) 
{
    int msgs_available;

    debugOutput(_debugUart,(char*)"+CALLED getSMS()\n");
    CHK_WNCFE((_pwnc->getWncStatus()==FATAL_FLAG), fail);

    _pwnc_mutex.lock();
    msgs_available = _pwnc->readUnreadSMSText(&m_smsmsgs, true);
    _pwnc_mutex.unlock();

    if( msgs_available ) {
        debugOutput(_debugUart,(char*)"+Have %d unread texts present\n",m_smsmsgs.msgCount);
        for( int i=0; i< m_smsmsgs.msgCount; i++ ) {
            m_MsgText_array[i].number = m_smsmsgs.e[i].number;
            m_MsgText_array[i].date   = m_smsmsgs.e[i].date;
            m_MsgText_array[i].time   = m_smsmsgs.e[i].time;
            m_MsgText_array[i].msg    = m_smsmsgs.e[i].msg;
            pmsg[i] = (IOTSMS*)&m_MsgText_array[i];
            }
        debugOutput(_debugUart,(char*)"+DONE getting messages\n");
        msgs_available = m_smsmsgs.msgCount;
        }
    debugOutput(_debugUart,(char*)"+EXIT getSMS\n");
    return msgs_available;
}


/*-------------------------------------------------------------------------
 * send a message to the specified user number. 
 *
 * input: string containing users number
 *        string with users message
 * ouput: none
 *
 * return: true if no problems occures, false if failed to send
 */
int WNC14A2AInterface::sendIOTSms(const string& number, const string& message) 
{

    debugOutput(_debugUart,(char*)"+CALLED sendIOTSms(%s,%s)\n",number.c_str(), message.c_str());
    _pwnc_mutex.lock();
    int i =  _pwnc->sendSMSText((char*)number.c_str(), message.c_str());
    _pwnc_mutex.unlock();

    return i;
}

//
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
//      NetworkStack API's that are not support in the WNC14A2A
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
//-------------------------------------------------------------------------
//

int inline WNC14A2AInterface::socket_accept(nsapi_socket_t server, nsapi_socket_t *handle, SocketAddress *address) 
{
    debugOutput(_debugUart,(char*)"+CALLED socket_accept()\n");
    _errors = NSAPI_ERROR_UNSUPPORTED;
    return -1;
}

int inline WNC14A2AInterface::socket_bind(void *handle, const SocketAddress &address) 
{
    debugOutput(_debugUart,(char*)"+CALLED socket_bind()\n");
    _errors = NSAPI_ERROR_UNSUPPORTED;
    return -1;
}


int inline WNC14A2AInterface::socket_listen(void *handle, int backlog)
{
   debugOutput(_debugUart,(char*)"+CALLED socket_listen()\n");
    _errors = NSAPI_ERROR_UNSUPPORTED;
    return -1;
}