File content as of revision 30:1a647403171b:

#include "mbed.h"
#include <ctype.h>
#include "MDM.h"

#define TRACE           (0)?:printf
//#define DEBUG         // enable this for AT command debugging
#define PROFILE         "0"   // this is the psd profile used
#define MAX_SIZE        256  // max expected messages
// some helper 
#define ISSOCKET(s)     (((s) >= 0) && ((s) < (sizeof(_sockets)/sizeof(*_sockets))))
#define IPSTR           "%d.%d.%d.%d"
#define IPNUM(addr)     (addr>>24)&0xff, (addr>>16)&0xff, (addr>>8)&0xff, addr&0xff
#define IPADR(a,b,c,d)  ((a<<24) | (b<<16) | (c<<8) | d)

#ifdef DEBUG
void dump(const char* buf, int len)
{
    while (len --) {
        char ch = *buf++;
        if      (ch == '\r') printf("\\r");
        else if (ch == '\n') printf("\\n");
        else if (ch >= 0x20) printf("%c", ch);
        else                 printf("\\x%02x", ch);
    }
}
#endif        

MDMParser::MDMParser(void)
{
    // device info
    _model   = MODEL_UNKNOWN;
    _sim     = SIM_UNKNOWN;
    *_ccid  = '\0';
    *_imsi  = '\0';
    *_imei  = '\0';
    // network info
    _net     = NET_UNKNOWN;
    _act     = ACT_UNKNOWN;
    _rssi    = 0;
    *_num    = '\0';
    *_opr    = '\0';
    // data network info
    _ip      = 0;
    for (int socket = 0; socket < sizeof(_sockets)/sizeof(*_sockets); socket++) {
        _sockets[socket].state = SOCK_FREE;
        _sockets[socket].pending = 0;
    }
}

int MDMParser::send(const char* buf, int len)
{
#ifdef DEBUG
    printf("   send \"");
    dump(buf,len);
    printf("\"\n");
#endif
    return _send(buf, len);
}

int MDMParser::sendFormated(const char* format, ...) {
    char buf[MAX_SIZE];
    va_list args;
    va_start(args, format);
    int len = vsnprintf(buf,sizeof(buf), format, args);
    va_end(args);
    return send(buf, len);
}

int MDMParser::waitFinalResp(_CALLBACKPTR cb /* = NULL*/, 
                             void* param /* = NULL*/, 
                             int timeout_ms /*= 5000*/)
{
    char buf[MAX_SIZE];
    Timer timer;
    timer.start();
    do {
        int ret = getLine(buf, sizeof(buf));
#ifdef DEBUG
        if ((ret != WAIT) && (ret != NOT_FOUND))
        {
            printf("   line %06X \"", ret);
            dump(buf, LENGTH(ret));
            printf("\"\n");
        }
#endif        
        if ((ret != WAIT) && (ret != NOT_FOUND))
        {
            int type = TYPE(ret);
            if (type == TYPE_OK)        return OK;
            if (type == TYPE_ERROR)     return ERROR;
            if (type == TYPE_PROMPT)    return PROMPT;
            // handle unsolicited commands here
            if (type == TYPE_PLUS) {
                const char* cmd = buf+3;
                int a, b, c, d;
                char s[32];

                // +CSQ: <rssi>,<qual>
                if (sscanf(cmd, "CSQ: %d,%d",&a,&b) == 2) {
                    if (a != 99) _rssi = -113 + 2*a;  // 0: -113 1: -111 ... 30: -53 dBm with 2 dBm steps
                    //if (b != 99) int qual = b;  // 
                // Socket Specific Command ---------------------------------
                // +UUSORD: <socket>,<length>
                } else if ((sscanf(cmd, "UUSORD: %d,%d", &a, &b) == 2) && 
                    ISSOCKET(a) && (_sockets[a].state == SOCK_CONNECTED)) {
                    TRACE("Socket %d: %d bytes pending\n", a, b);
                    _sockets[a].pending = b;
                // +UUSORF: <socket>,<length>
                } else if ((sscanf(cmd, "UUSORF: %d,%d", &a, &b) == 2) && 
                    ISSOCKET(a) && (_sockets[a].state == SOCK_CONNECTED)) {
                    TRACE("Socket %d: %d bytes pending\n", a, b);
                    _sockets[a].pending = b;
                // +UUSOCL: <socket>
                } else if ((sscanf(cmd, "UUSOCL: %d", &a) == 1) && 
                    ISSOCKET(a) && (_sockets[a].state == SOCK_CONNECTED)) {
                    TRACE("Socket %d: closed by remote host\n", a);
                    _sockets[a].state = SOCK_CREATED/*=CLOSED*/;
                }                
                if (_model == MODEL_LISA_C200) {
                    // CDMA Specific -------------------------------------------
                    // +CREG: <n><SID>,<NID>,<stat>
                    if (sscanf(cmd, "CREG: %*d,%*d,%*d,%d",&a) == 1) {
                        if      (a == 0) _net = NET_NONE;     // not registered, home network
                        else if (a == 1) _net = NET_HOME;     // registered, home network
                        else if (a == 2) _net = NET_NONE;     // not registered, but MT is currently searching a new operator to register to
                        else if (a == 3) _net = NET_DENIED;   // registration denied
                        else if (a == 5) _net = NET_ROAMING;  // registered, roaming
                        _act = ACT_CDMA;
                    // +CSS: <mode>[,<format>,<oper>[,<AcT>]]
                    } else if (sscanf(cmd, "CSS %*c,%2s,%*d",s) == 1) {
                        //_net = (strcmp("Z", s) == 0) ? NET_UNKNOWN : NET_HOME;
                    // +CMIP: xxx.xxx.xxx.xxx
                    } else if (sscanf(cmd, "CMIP: " IPSTR, &a,&b,&c,&d) == 4) {
                        _ip = IPADR(a,b,c,d);
                    }
                } else {
                    // GSM/UMTS Specific -------------------------------------------
                    // +CREG: <n>, <stat>[,<lac>,<ci>[,AcT]]
                    b = 255;
                    if (sscanf(cmd, "CREG: %*d,%d,%*d,%d",&a,&b) >= 1) {
                        // network status
                        if      (a == 0) _net = NET_NONE;     // 0: not registered, home network
                        else if (a == 1) _net = NET_HOME;     // 1: registered, home network
                        else if (a == 2) _net = NET_NONE;     // 2: not registered, but MT is currently searching a new operator to register to
                        else if (a == 3) _net = NET_DENIED;   // 3: registration denied
                        else if (a == 4) _net = NET_UNKNOWN;  // 4: unknown
                        else if (a == 5) _net = NET_ROAMING;  // 5: registered, roaming
                        // access technology
                        if      (b == 0) _act = ACT_GSM;      // 0: GSM
                        else if (b == 1) _act = ACT_GSM;      // 1: GSM COMPACT
                        else if (b == 2) _act = ACT_UTRAN;    // 2: UTRAN
                        else if (b == 3) _act = ACT_EDGE;     // 3: GSM with EDGE availability
                        else if (b == 4) _act = ACT_UTRAN;    // 4: UTRAN with HSDPA availability
                        else if (b == 5) _act = ACT_UTRAN;    // 5: UTRAN with HSUPA availability
                        else if (b == 6) _act = ACT_UTRAN;    // 6: UTRAN with HSDPA and HSUPA availability
                    // +COPS: <mode>[,<format>,<oper>[,<AcT>]]
                    } else if (sscanf(cmd, "COPS: %*d,%*d,\"%[^\"]\",%d",s,&b) >= 1) {
                        strcpy(_opr,s);
                        if      (a == 0) _act = ACT_GSM;      // 0: GSM, 
                        else if (a == 2) _act = ACT_UTRAN;    // 2: UTRAN
                    // +CPIN: <code>
                    } else if (sscanf(cmd, "CPIN: %7s",s) == 1) {
                        _sim = (strcmp("READY", s) == 0) ? SIM_READY : SIM_UNKNOWN;
                    // +CNUM: <code>
                    } else if (sscanf(cmd, "CNUM: \"My Number\",\"%31[^\"]\",%d", s, &a) == 2) {
                        if ((a == 129) || (a == 145)) strncpy(_num, s, sizeof(_num));
                    // +UPSND=<profile_id>,<param_tag>[,<dynamic_param_val>]
                    } else if (sscanf(cmd, "UPSND: " PROFILE ",0,\"" IPSTR "\"", &a,&b,&c,&d) == 4) {
                        _ip = IPADR(a,b,c,d);
                    // +UUPSDD: <profile_id> 
                    } else if (sscanf(cmd, "UUPSDD: %d",&a) == 1) {
                        if (*PROFILE == a) _ip = 0;
                    }
                }
            }
            if (cb) {
                int len = LENGTH(ret);
                int ret = cb(type, buf, len, param);
                if (WAIT != ret)
                    return ret; 
            }
        }
        // relax a bit
        wait_ms(10); 
    }
    while (timer.read_ms() < timeout_ms);
    timer.stop();
    timer.reset();
    return WAIT;
}

// ----------------------------------------------------------------

int MDMParser::_cbATI(int type, const char* buf, int len, Model* model)
{
    if ((type == TYPE_UNKNOWN) && model) {
        if (strstr(buf, "SARA-G350")) {
            *model = MODEL_SARA_G350;
            /*TRACE("Identified Model: SARA-G350 2G\n")*/;
        } else if (strstr(buf, "LISA-U200")) {
            *model = MODEL_LISA_U200;
            /*TRACE("Identified Model: LISA-U200 2G/3G\n")*/;
        } else if (strstr(buf, "LISA-C200")) {
            *model= MODEL_LISA_C200;
            /*TRACE("Identified Model: LISA-C200 CDMA\n")*/;
        }
    }
    return WAIT;
}

bool MDMParser::init(const char* pin, DevStatus* status)
{
    for(int i = 0; i < 5; i++) {
        // check interface and disable local echo
        sendFormated("AT\r\n");
        if(OK == waitFinalResp())
            break;
    }
    // echo off
    sendFormated("AT E0\r\n");
    if(OK != waitFinalResp())
        return false;
    // enable verbose error messages
    sendFormated("AT+CMEE=2\r\n");
    if(OK != waitFinalResp())
        return false;
    // set baud rate
    sendFormated("AT+IPR=115200\r\n");
    if (OK != waitFinalResp())
        return false;
    wait_ms(40);
    // identify the module 
    sendFormated("ATI\r\n");
    if (OK != waitFinalResp(_cbATI, &_model))
        return false;
    if (_model == MODEL_UNKNOWN)
        return false;
    // model specific init
    if (_model == MODEL_LISA_C200) {
        // disable flow control
        sendFormated("AT+IFC=0,0\r\n");
        if (OK != waitFinalResp())
            return false;
        // Return the pseudo ESN or MEID
        sendFormated("AT+GSN\r\n");
        if (OK != waitFinalResp(_cbGSN, _imei))
            return false;
    } else {
        // disable flow control
        sendFormated("AT&K0\r\n");
        if (OK != waitFinalResp())
            return false;
        // enable power saving
        sendFormated("AT+UPSV=1\r\n");
        if (OK != waitFinalResp())
            return false;
        // enable the network identification feature 
        if (_model == MODEL_LISA_U200) {
            sendFormated("AT+UGPIOC=20,2\r\n");
            if (OK != waitFinalResp())
                return false;
        } else {
            sendFormated("AT+UGPIOC=16,2\r\n");
            if (OK != waitFinalResp())
                return false;
        }
        // Enter PIN if needed
        if (pin) {
            sendFormated("AT+CPIN=%s\r\n", pin);
            if (OK != waitFinalResp())
                return false;
        }
        // check the sim card
        for (int i = 0; i < 5; i++) {
            sendFormated("AT+CPIN?\r\n");
            int ret = waitFinalResp();
            if ((OK != ret) && (ERROR != ret))
                return false;
            if (_sim != SIM_UNKNOWN)
                break;
            wait_ms(1000);
        }
        if (_sim != SIM_READY)
            return false;
        // Returns the ICCID (Integrated Circuit Card ID) of the SIM-card. 
        // ICCID is a serial number identifying the SIM.
        sendFormated("AT+CCID\r\n");
        if (OK != waitFinalResp(_cbCCID, _ccid))
            return false;
        // Returns the product serial number, IMEI (International Mobile Equipment Identity)
        sendFormated("AT+CGSN\r\n");
        if (OK != waitFinalResp(_cbCGSN, _imei))
            return false;
        // Setup SMS in text mode 
        sendFormated("AT+CMGF=1\r\n");
        if (OK != waitFinalResp())
            return false;
        // Configure New message indication
        //sendFormated("AT+CNMI=2,1,0,0,0\r\n");
        //if (OK != waitFinalResp())
        //    return false;
            
    } 
    // Request IMSI (International Mobile Subscriber Identification)
    sendFormated("AT+CIMI\r\n");
    if (OK != waitFinalResp(_cbCIMI, _imsi))
        return false;
    if (status)
    {
        status->model = _model;
        status->sim   = _sim;
        status->ccid  = _ccid;
        status->imsi  = _imsi;    
        status->imei  = _imei;
    }
    return true; 
}

int MDMParser::_cbCCID(int type, const char* buf, int len, char* ccid)
{
    if ((type == TYPE_PLUS) && ccid){
        if (sscanf(buf, "\r\n+CCID: %[^\r]\r\n", ccid) == 1)
            /*TRACE("Got CCID: %s\n", ccid)*/;
    }
    return WAIT;
}

int MDMParser::_cbGSN(int type, const char* buf, int len, char* imei)
{
    if ((type == TYPE_UNKNOWN) && imei){
        if (sscanf(buf, "\r\n%[^\r]\r\n%*[^\r]\r\n", imei) == 1)
            /*TRACE("Got IMEI: %s\n", imei)*/;
    }
    return WAIT;
}

int MDMParser::_cbCGSN(int type, const char* buf, int len, char* imei)
{
    if ((type == TYPE_UNKNOWN) && imei){
        if (sscanf(buf, "\r\n%[^\r]\r\n", imei) == 1)
            /*TRACE("Got IMEI: %s\n", imei)*/;
    }
    return WAIT;
}

int MDMParser::_cbCIMI(int type, const char* buf, int len, char* imsi)
{
    if ((type == TYPE_UNKNOWN) && imsi) {
        if (sscanf(buf, "\r\n%[^\r]\r\n", imsi) == 1)
            /*TRACE("Got IMSI: %s\n", imsi)*/;
    }
    return WAIT;
}

bool MDMParser::checkNetStatus(NetStatus* status /*= NULL*/)
{
    // check registration
    sendFormated("AT+CREG?\r\n");
    if (OK != waitFinalResp())
        return false;
    if ((_net != NET_ROAMING) && (_net != NET_HOME))
        return false;
    // check modem specific status messages 
    if (_model == MODEL_LISA_C200) {
        sendFormated("AT+CSS?\r\n");
        if (OK != waitFinalResp())
            return false;
        if ((_net != NET_ROAMING) && (_net != NET_HOME))
            return false;
    } else {
        // check operator selection 
        sendFormated("AT+COPS?\r\n");
        if (OK != waitFinalResp())
            return false;
        // Returns the MSISDNs related to this subscriber
        sendFormated("AT+CNUM\r\n");
        if (OK != waitFinalResp())
            return false;
    }  
    // Returns the signal strength indication
    sendFormated("AT+CSQ\r\n");
    if (OK != waitFinalResp())
        return false;
    if (status) {
        status->num = _num;
        status->opr = _opr;
        status->rssi = _rssi;
        status->net = _net;
        status->act = _act;
    }
    return true;
}

bool MDMParser::powerOff(void)
{
    sendFormated("AT+CPWROFF\r\n");
    if (OK != waitFinalResp(NULL,NULL,120))
        return false;
    return true;
}

// ----------------------------------------------------------------
// internet connection 

MDMParser::IP MDMParser::strToIp(const char* str)
{
    IP ip = 0;
    char* p = (char*)str;
    for(int i = 0; i < 4; i++) {
        ip |= atoi(p);
        p = strchr(p, '.');
        if (p == NULL) {
            break;
        }
        ip <<= 8;
        p++;
    }
    return ip;
}

bool MDMParser::join(const char* apn /*= NULL*/, const char* user /*= NULL*/, const char* password /*= NULL*/)
{
    if (_model == MODEL_LISA_C200) {
#ifdef TODO // TODO implement 
        // enable the 
        sendFormated("AT$QCMIPEP=1\r\n");
        if (OK != waitFinalResp())
            return false;
        //Get local IP address
        sendFormated("AT+CMIP?\r\n");
        if (OK != waitFinalResp())
            return false;
#endif
    } else { 
        // check gprs attach status 
        sendFormated("AT+CGATT?\r\n");
        if (OK != waitFinalResp())
            return false;
         // Set up the APN
        if (apn) {
            sendFormated("AT+UPSD=" PROFILE ",1,\"%s\"\r\n", apn);
            if (OK != waitFinalResp())
                return false;
        }
        if (user) {    
            sendFormated("AT+UPSD=" PROFILE ",2,\"%s\"\r\n", user);
            if (OK != waitFinalResp())
                return false;
        }
        if (password) {
            sendFormated("AT+UPSD=" PROFILE ",3,\"%s\"\r\n", password);
            if (OK != waitFinalResp())
                return false;
        }
        // Set up the dynamic IP address assignment.
        sendFormated("AT+UPSD=" PROFILE ",7,\"0.0.0.0\"\r\n");
        if (OK != waitFinalResp())
            return false;
        // Activate the profile and make connection
        sendFormated("AT+UPSDA=" PROFILE ",3\r\n");
        if (OK != waitFinalResp())
            return false;
        //Get local IP address
        sendFormated("AT+UPSND=" PROFILE ",0\r\n");
        if (OK != waitFinalResp())
            return false;
    }
    if (!_ip)
        return false;
    TRACE("Got IP address: " IPSTR "\n",  IPNUM(_ip));
    return true;
}

bool MDMParser::disconnect(void)
{
    if (_ip == 0)
        return true;
    if (_model == MODEL_LISA_C200) {
#ifdef TODO // TODO implement 
        sendFormated("AT$QCMIPEP=0\r\n");
#endif
    } else { 
        sendFormated("AT+UPSDA=" PROFILE ",4\r\n");
    }
    if (OK != waitFinalResp())
        return false;
    _ip = 0;
    return true;
}

int MDMParser::_cbUDNSRN(int type, const char* buf, int len, IP* ip)
{
    if ((type == TYPE_PLUS) && ip) {
        buf += 3;
        int a,b,c,d;
        if (sscanf(buf, "UDNSRN: \""IPSTR"\"", &a,&b,&c,&d) == 4)
            *ip = IPADR(a,b,c,d);
    }
    return WAIT;
}

bool MDMParser::gethostbyname(const char* host, IP* ip)
{
    char ipstr[16];
    IP addr = strToIp(host);
    *ip = 0;
    snprintf(ipstr, sizeof(ipstr), IPSTR, IPNUM(addr));
    if (strcmp(ipstr, host) == 0) {
        *ip = addr;
        return true;
    }
    sendFormated("AT+UDNSRN=0,\"%s\"\r\n", host);
    if (OK != waitFinalResp(_cbUDNSRN, ip))
        return false;
    return *ip != 0;
}

// ----------------------------------------------------------------
// sockets

int MDMParser::_cbUSOCR(int type, const char* buf, int len, int* socket)
{
    if ((type == TYPE_PLUS) && socket) {
        const char* p = strstr(buf,"+USOCR: "); 
        if (p)
            *socket = atoi(p+8);
    }
    return WAIT;
}

int MDMParser::socketSocket(IpProtocol ipproto)
{
    const char* cmd;
    if(ipproto == IPPROTO_TCP) {
        cmd = "AT+USOCR=6\r\n";
    } else if(ipproto == IPPROTO_UDP) {
        cmd = "AT+USOCR=17\r\n";
    } else { // other types not supported
        return SOCKET_ERROR;
    }
    sendFormated(cmd);
    int socket = -1;
    if (OK != waitFinalResp(_cbUSOCR, &socket))
        return SOCKET_ERROR;
    if (!ISSOCKET(socket) || (_sockets[socket].state != SOCK_FREE))
        return SOCKET_ERROR;
    // successfull
    _sockets[socket].state = SOCK_CREATED;
    _sockets[socket].pending = 0;
    return socket;
}

bool MDMParser::socketConnect(int socket, const char * host, int port)
{
    IP ip;
    if (!gethostbyname(host, &ip))
        return false;
    // connect to socket
    if (!ISSOCKET(socket) || (_sockets[socket].state != SOCK_CREATED))
        return false;
    sendFormated("AT+USOCO=%d,\"" IPSTR "\",%d\r\n", socket, IPNUM(ip), port);
    if (OK != waitFinalResp())
        return false;
    _sockets[socket].state = SOCK_CONNECTED;
    return true;
}

bool  MDMParser::socketClose(int socket)
{
    if (!ISSOCKET(socket) || (_sockets[socket].state != SOCK_CONNECTED))
        return false;
    sendFormated("AT+USOCL=%d\r\n", socket);
    if (OK != waitFinalResp())
        return false;
    return true;
}

bool  MDMParser::socketFree(int socket)
{
    socketClose(socket);
    if (!ISSOCKET(socket) || (_sockets[socket].state != SOCK_CREATED))
        return false;
    _sockets[socket].state = SOCK_FREE;
    return true;
}

int MDMParser::socketSend(int socket, const char * buf, int len)
{
    if(len > 0) {
        sendFormated("AT+USOWR=%d,%d\r\n",socket,len);
        if (PROMPT != waitFinalResp())
            return SOCKET_ERROR;
        wait_ms(50);
        send(buf, len);
        if (OK != waitFinalResp()) 
            return SOCKET_ERROR;
    }
    return len;
}

int MDMParser::socketSendTo(int socket, IP ip, int port, const char * buf, int len)
{
    if(len > 0) {
        sendFormated("AT+USOWR=%d,\"" IPSTR "\",%d,%d\r\n",socket,IPNUM(ip),port,len);
        if (PROMPT != waitFinalResp())
            return SOCKET_ERROR;
        wait_ms(50);
        send(buf, len);
        if (OK != waitFinalResp()) 
            return SOCKET_ERROR;
    }
    return len;
}

int MDMParser::socketReadable(int socket)
{
    if (!ISSOCKET(socket) || (_sockets[socket].state != SOCK_CONNECTED))
        return SOCKET_ERROR;
    // allow to receive unsolicited commands 
    waitFinalResp(NULL, NULL, 0);
    if (_sockets[socket].state != SOCK_CONNECTED)
        return SOCKET_ERROR;
    return _sockets[socket].pending;
}

int MDMParser::_cbUSORD(int type, const char* buf, int len, char* out)
{
    if ((type == TYPE_PLUS) && out) {
        int sz, sk;
        if ((sscanf(buf, "\r\n+USORD: %d,%d,", &sk, &sz) == 2) && 
            (buf[len-sz-2] == '\"') && (buf[len-1] == '\"')) {
            memcpy(out, &buf[len-1-sz], sz);
        }
    }
    return WAIT;
}

int MDMParser::socketRecv(int socket, char* buf, int len)
{
    int cnt = 0;
    if (!ISSOCKET(socket))
        return SOCKET_ERROR;
    memset(buf, '\0', len);
    while (len) {
        int blk = MAX_SIZE - 64; // still need space for headers and unsolicited  commands 
        if (_sockets[socket].state != SOCK_CONNECTED)
            return cnt ? cnt : SOCKET_ERROR;
        if (_sockets[socket].pending < blk)
            blk = _sockets[socket].pending;
        if (len < blk) blk = len;
        if (blk) {
             sendFormated("AT+USORD=%d,%d\r\n",socket, blk);
            if (OK != waitFinalResp(_cbUSORD, buf)) {
                return cnt ? cnt : SOCKET_ERROR;
            }
            len -= blk;
            cnt += blk;
            buf += blk;
            _sockets[socket].pending -= blk;
        } else {
            // allow to receive unsolicited commands 
            waitFinalResp(NULL, NULL, 10);
        }
    }
    return cnt;
}

int MDMParser::_cbUSORF(int type, const char* buf, int len, USORFparam* param)
{
    if ((type == TYPE_PLUS) && param) {
        int sz, sk, p, a,b,c,d;
        if ((sscanf(buf, "\r\n+USORF: %d,\""IPSTR"\",%d,%d,", 
            &sk,&a,&b,&c,&d,&p,&sz) == 7) && 
            (buf[len-sz-2] == '\"') && (buf[len-1] == '\"')) {
            memcpy(param->buf, &buf[len-1-sz], sz);
            param->ip = IPADR(a,b,c,d);
            param->port = p;
        }
    }
    return WAIT;
}

int MDMParser::socketRecvFrom(int socket, char* buf, int len, IP* ip)
{
    int cnt = 0;
    if (!ISSOCKET(socket))
        return SOCKET_ERROR;
    memset(buf, '\0', len);
    while (len) {
        int blk = MAX_SIZE - 64; // still need space for headers and unsolicited commands 
        if (_sockets[socket].state != SOCK_CONNECTED)
            return cnt ? cnt : SOCKET_ERROR;
        if (_sockets[socket].pending < blk)
            blk = _sockets[socket].pending;
        if (len < blk) blk = len;
        if (blk) {
            sendFormated("AT+USORF=%d,%d\r\n",socket, blk);
            USORFparam param;
            param.buf = buf;
            if (OK != waitFinalResp(_cbUSORF, &param)) {
                return cnt ? cnt : SOCKET_ERROR;
            }
            *ip = param.ip;
            //*port = param.port;
            len -= blk;
            cnt += blk;
            buf += blk;
            _sockets[socket].pending -= blk;
        } else {
            // allow to receive unsolicited commands 
            waitFinalResp(NULL, NULL, 10);
        }
    }
    return cnt;
}

// ----------------------------------------------------------------
int MDMParser::_cbCPMS(int type, const char* buf, int len, int* num)
{ 
    if ((type == TYPE_PLUS) && num) {
        // AT+CPMS: <used1>,<total1>,<used2>,<total2>,<used3>,<total3>;
        if (sscanf(buf, "\r\n+CPMS: %d,%*d", num) == 1)
            /*nothing*/;
    }
    return WAIT;
}

int MDMParser::smsCount(void)
{
    int num = 0;
    sendFormated("AT+CPMS=\"ME\"\r\n");
    if (OK != waitFinalResp(_cbCPMS,&num)) {
        return 0;
    }
    return num;
}

bool MDMParser::smsSend(const char* num, const char* buf)
{
    sendFormated("AT+CMGS=\"%s\"\r",num);
    if (PROMPT != waitFinalResp()) {
        return false;
    }
    send(buf, strlen(buf));
    const char ctrlZ = 0x1A;
    send(&ctrlZ, sizeof(ctrlZ));
    if (OK != waitFinalResp()) {
        return false;
    }
    return true;
}

bool MDMParser::smsDelete(int ix)
{
    sendFormated("AT+CMGD=%d\r\n",ix);
    if (OK != waitFinalResp()) {
        return false;
    }
    return true;
}

int MDMParser::_cbCMGR(int type, const char* buf, int len, CMGRparam* param)
{
    if (param) {
        if (type == TYPE_PLUS) {
            if (sscanf(buf, "\r\n+CMGR: \"%*[^\"]\",\"%[^\"]", param->num) == 1) {
            }
        } else if ((type == TYPE_UNKNOWN) && (buf[len-2] == '\r') && (buf[len-1] == '\n')) {
            memcpy(param->buf, buf, len-2);
            param->buf[len-2] = '\0';
        }
    }
    return WAIT;
}

bool MDMParser::smsRead(int ix, char* num, char* buf, int len)
{
    CMGRparam param;
    param.num = num;
    param.buf = buf;
    sendFormated("AT+CMGR=%d\r\n",ix);
    if (OK != waitFinalResp(_cbCMGR, &param)) {
        return false;
    }
    return true;
}
    
// ----------------------------------------------------------------
  
int MDMParser::_cbCUSD(int type, const char* buf, int len, char* resp)
{
    if ((type == TYPE_PLUS) && resp) {
        // +USD: \"%*[^\"]\",\"%[^\"]\",,\"%*[^\"]\",%d,%d,%d,%d,\"*[^\"]\",%d,%d"..);
        if (sscanf(buf, "\r\n+CUSD: %*d,\"%[^\"]\",%*d", resp) == 1) {
            /*nothing*/            
        }
    }
    return WAIT;
}  
int MDMParser::ussdCommand(const char* cmd, char* buf, int len)
{
    *buf = '\0';
    sendFormated("AT+CUSD=1,\"%s\"\r\n",cmd);
    if (OK != waitFinalResp(_cbCUSD, buf)) {
        return -1;
    }
    return strlen(buf);
}
       
// ----------------------------------------------------------------
int MDMParser::_parseMatch(Pipe<char>* pipe, int len, const char* sta, const char* end)
{
    int o = 0;
    if (sta) {
        while (*sta) {
            if (++o > len)                  return WAIT;
            char ch = pipe->next();
            if (*sta++ != ch)               return NOT_FOUND;
        }
    }
    if (!end)                               return o; // no termination
    int x = 0;
    while (end[x]) {
        if (++o > len)                      return WAIT;
        char ch = pipe->next();
        x = (end[x] == ch) ? x + 1 : 
            (end[0] == ch) ? 1 : 
                            0;
    }
    return o;
}

int MDMParser::_parseFormated(Pipe<char>* pipe, int len, const char* fmt)
{
    int o = 0;
    int num = 0;
    if (fmt) {
        while (*fmt) {
            if (++o > len)                  return WAIT;
            char ch = pipe->next();
            if (*fmt == '%') {
                fmt++;
                if (*fmt == 'd') { // numeric
                    fmt ++;
                    num = 0;
                    while (ch >= '0' && ch <= '9') {
                        num = num * 10 + (ch - '0'); 
                        if (++o > len)      return WAIT;
                        ch = pipe->next();
                    }
                }   
                else if (*fmt == 'c') { // char buffer (takes last numeric as length)
                    fmt ++;
                    while (num --) {
                        if (++o > len)      return WAIT;
                        ch = pipe->next();
                    }   
                }
            }
            if (*fmt++ != ch)               return NOT_FOUND;
        }
    }
    return o; 
}


int MDMParser::_getLine(Pipe<char>* pipe, char* buf, int len)
{
    int unkn = 0;
    int sz = pipe->size();
    int fr = pipe->free();
    if (len > sz)
        len = sz;
    while (len > 0)
    {
        static struct { 
              const char* fmt;                              int type; 
        } lutF[] = {
            { "\r\n+USORD: %d,%d,\"%c\"",                   TYPE_PLUS       },
            { "\r\n+USORF: %d,\""IPSTR"\",%d,%d,\"%c\"",    TYPE_PLUS       },
        };
        static struct { 
              const char* sta;          const char* end;    int type; 
        } lut[] = {
            { "\r\nOK\r\n",             NULL,               TYPE_OK         },
            { "\r\nERROR\r\n",          NULL,               TYPE_ERROR      },
            { "\r\n+CME ERROR:",        "\r\n",             TYPE_ERROR      },
            { "\r\n+CMS ERROR:",        "\r\n",             TYPE_ERROR      },
            { "\r\nRING\r\n",           NULL,               TYPE_RING       },
            { "\r\nCONNECT\r\n",        NULL,               TYPE_CONNECT    },
            { "\r\nNO CARRIER\r\n",     NULL,               TYPE_NOCARRIER  },
            { "\r\nNO DIALTONE\r\n",    NULL,               TYPE_NODIALTONE },
            { "\r\nBUSY\r\n",           NULL,               TYPE_BUSY       },
            { "\r\nNO ANSWER\r\n",      NULL,               TYPE_NOANSWER   },
            { "\r\n+",                  "\r\n",             TYPE_PLUS       },
            { "\r\n@",                  NULL,               TYPE_PROMPT     }, // Sockets
            { "\r\n>",                  NULL,               TYPE_PROMPT     }, // SMS
        };
        for (int i = 0; i < sizeof(lutF)/sizeof(*lutF); i ++) {
            pipe->set(unkn);
            int ln = _parseFormated(pipe, len, lutF[i].fmt);
            if (ln == WAIT && fr)                       
                return WAIT;
            if ((ln != NOT_FOUND) && (unkn > 0))  
                return pipe->get(buf, unkn);
            if (ln > 0)
                return lutF[i].type  | pipe->get(buf, ln);
        }
        for (int i = 0; i < sizeof(lut)/sizeof(*lut); i ++) {
            pipe->set(unkn);
            int ln = _parseMatch(pipe, len, lut[i].sta, lut[i].end);
            if (ln == WAIT && fr)                       
                return WAIT;
            if ((ln != NOT_FOUND) && (unkn > 0))  
                return pipe->get(buf, unkn);
            if (ln > 0)
                return lut[i].type | pipe->get(buf, ln);
        }
        // UNKNOWN
        unkn ++;
        len--;
    }
    return WAIT;
}

// ----------------------------------------------------------------
// Serial Implementation 
// ----------------------------------------------------------------

MDMSerial::MDMSerial(PinName tx /*= MDMTXD*/, PinName rx /*= MDMRXD*/, 
            int baudrate /*= MDMBAUD*/,
#if DEVICE_SERIAL_FC
            PinName rts /*= MDMRTS*/, PinName cts /*= MDMCTS*/, 
#endif
            int rxSize /*= 256*/, int txSize /*= 128*/) : 
#if DEVICE_SERIAL_FC
            SerialPipe(tx, rx, rts, cts, rxSize, txSize)
#else
            SerialPipe(tx, rx, rxSize, txSize)
#endif
{
    baud(baudrate);
}

int MDMSerial::_send(const void* buf, int len)   
{ 
    return put((const char*)buf, len, true/*=blocking*/); 
}

int MDMSerial::getLine(char* buffer, int length)
{
    return _getLine(&_pipeRx, buffer, length);
}

// ----------------------------------------------------------------
// USB Implementation 
// ----------------------------------------------------------------

#ifdef HAVE_MDMUSB
// TODO properly implement with USB 
MDMUsb::MDMUsb(void)                             { }
int MDMUsb::_send(const void* buf, int len)      { return len; }
int MDMUsb::getLine(char* buffer, int length)    { return NOT_FOUND; }
#endif