ESP8266 Socket Library. AT Thinker firmware.

Dependents:   ESP8266_MQTT_HelloWorld ESP8266_IFTTT_Test ECE_4180_Lab_4 websocketmbed ... more

Fork of ESP8266Interface by ESP8266

This repository has been superceded

This project has moved to https://developer.mbed.org/teams/ESP8266/code/esp8266-driver/

This library works with the AT Thinker firmware.

Note

This library is currently in Beta. It is not feature complete and has some bugs, proceed with caution! Fixes and patches are welcome and appreciated!

Currently the ESP8266Interface Library has the following Abilities:

Working

  • TCP Client
  • UDP Client
  • Transparent mode (single connection of 1 type at a time)
  • Station Mode (connects to AP)

To be implemented

  • TCP Server
  • UDP Server
  • Multi Connection Mode (able to have up to 5 sockets at a time)
  • AP Mode (Make ESP Chip act like access point)
  • DNS Support (currently websites must be looked up by IP)
  • Error Recovery

Nice but not necessary

  • colorized text for ESP AT Commands in Command line (easier to differentiate from other text)

ESP8266/ESP8266.cpp

Committer:
sarahmarshy
Date:
2015-06-10
Revision:
48:03fd9333670d
Parent:
47:1f4dd0e91837

File content as of revision 48:03fd9333670d:

/* Copyright (C) 2012 mbed.org, MIT License
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
 * and associated documentation files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or
 * substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

#include "mbed.h"
#include "ESP8266.h"
#include "Endpoint.h"
#include <string>
#include <algorithm>

//Debug is disabled by default
#if 0
#define DBG(x, ...)  printf("[ESP8266 : DBG]"x" \t[%s,%d]\r\n", ##__VA_ARGS__,__FILE__,__LINE__); 
#define WARN(x, ...) printf("[ESP8266 : WARN]"x" \t[%s,%d]\r\n", ##__VA_ARGS__,__FILE__,__LINE__); 
#define ERR(x, ...)  printf("[ESP8266 : ERR]"x" \t[%s,%d]\r\n", ##__VA_ARGS__,__FILE__,__LINE__); 
#else
#define DBG(x, ...) //wait_us(10);
#define WARN(x, ...) //wait_us(10);
#define ERR(x, ...)
#endif

#if 0
#define INFO(x, ...) printf("[ESP8266 : INFO]"x" \t[%s,%d]\r\n", ##__VA_ARGS__,__FILE__,__LINE__); 
#else
#define INFO(x, ...)
#endif

#define ESP_MAX_TRY_JOIN 3
#define ESP_MAXID 4 // the largest possible ID Value (max num of sockets possible)

ESP8266 * ESP8266::inst;
char* ip = NULL;

ESP8266::ESP8266(PinName tx, PinName rx, PinName reset, const char *ssid, const char *phrase, uint32_t baud) :
    wifi(tx, rx), reset_pin(reset), buf_ESP8266(ESP_MBUFFE_MAX)
{
    INFO("Initializing ESP8266 object");
    memset(&state, 0, sizeof(state));


    strcpy(this->ssid, ssid);
    strcpy(this->phrase, phrase);
    inst = this;
    attach_rx(false);

    wifi.baud(baud); // initial baud rate of the ESP8266

    state.associated = false;
    state.cmdMode = false;
}

bool ESP8266::join()
{
    sendCommand( "AT+CWMODE=1", "change", NULL, 1000);
    string cmd="AT+CWJAP=\""+(string)this->ssid+"\",\""+(string)this->phrase+"\"";
    if( sendCommand( cmd.c_str(), "OK", NULL, 10000) ) {
        // successfully joined the network
        state.associated = true;
        INFO("ssid: %s, phrase: %s", this->ssid, this->phrase);
        return true;
    }
    return false;
}

bool ESP8266::connect()
{
    sendCommand("AT+CWDHCP=1,1","OK",NULL,1000); // DHCP Enabled in Station Mode
    return ESP8266::join();
}

bool ESP8266::is_connected()
{
    return true;
}

bool ESP8266::start(bool type,char* ip, int port, int id)
{
    // Error Check
    if(id > ESP_MAXID) {
        ERR("startUDPMulti: max id is: %d, id given is %d",ESP_MAXID,id);
        return false;
    }
    // Single Connection Mode
    if(id < 0) {
        DBG("Start Single Connection Mode");
        char portstr[5];
        char idstr[2];
        bool check [3] = {0};
        sprintf(idstr,"%d",id);
        sprintf(portstr, "%d", port);
        switch(type) {
            case ESP_UDP_TYPE : //UDP
                check[0] = sendCommand(( "AT+CIPSTART=\"UDP\",\"" + (string) ip + "\"," + (string) portstr ).c_str(), "OK", NULL, 10000);
                break;
            case ESP_TCP_TYPE : //TCP
                check[0] = sendCommand(( "AT+CIPSTART=\"TCP\",\"" + (string) ip + "\"," + (string) portstr ).c_str(), "OK", NULL, 10000);
                break;
            default:
                ERR("Default hit for starting connection, this shouldnt be possible!!");
                break;
        }
        check[1] = sendCommand("AT+CIPMODE=1", "OK", NULL, 1000);// go into transparent mode
        check[2] = sendCommand("AT+CIPSEND", ">", NULL, 1000);// go into transparent mode
        // check that all commands were sucessful
        if(check[0] and check[1] and check[2]) {
            state.cmdMode = false;
            return true;
        } else {
            ERR("startUDPTransparent Failed for ip:%s, port:%d",ip,port);
            return false;
        }
    }
    // Multi Connection Mode
    else {
        //TODO: impliment Multi Connection Mode
        ERR("Not currently Supported!");
        return false;
        
//        DBG("Start Multi Connection Mode");
//        char portstr[5];
//        char idstr[2];
//        bool check [3] = {0};
//        sprintf(idstr,"%d",id);
//        sprintf(portstr, "%d", port);
//        switch(type) {
//            case ESP_UDP_TYPE : //UDP
//                check[0] = sendCommand(( "AT+CIPSTART=" + (string) idstr + ",\"UDP\",\"" + (string) ip + "\"," + (string) portstr ).c_str(), "OK", NULL, 10000);
//                break;
//            case ESP_TCP_TYPE : //TCP
//                check[0] = sendCommand(( "AT+CIPSTART=" + (string) idstr + ",\"TCP\",\"" + (string) ip + "\"," + (string) portstr ).c_str(), "OK", NULL, 10000);
//                break;
//            default:
//                ERR("Default hit for starting connection, this shouldnt be possible!!");
//                break;
//        }
    }
}

bool ESP8266::startUDP(char* ip, int port, int id, int length)
{
    char portstr[5];
    char idstr[1];
    char lenstr[2];
    
    sprintf(portstr, "%d", port);
    sprintf(idstr, "%d", id);
    sprintf(lenstr, "%d", length);
    
    sendCommand("AT+CIPMUX=1", "OK", NULL, 1000);
    sendCommand(( "AT+CIPSTART=" + string(idstr) + ",\"UDP\",\"" + (string) ip + "\"," + (string) portstr + ",1112,0").c_str(), "OK", NULL, 10000);
    sendCommand(("AT+CIPSEND=" + (string)idstr + "," +  (string)lenstr).c_str(), ">", NULL, 1000);// go into transparent mode
    DBG("Data Mode\r\n");
    state.cmdMode = false;

    return true;
}

bool ESP8266::startTCPServer(int port)
{
    bool command_results[3];
    command_results[0]=sendCommand("AT+CWMODE=3", "OK", NULL, 1000);
    command_results[1]=sendCommand("AT+CIPMUX=1", "OK", NULL, 1000);
    if(port == 333){
        command_results[2]=sendCommand("AT+CIPSERVER=1", "OK", NULL, 1000);
    }
    else{
        char portstr[5];
        sprintf(portstr, "%d", port);
        command_results[2]=sendCommand(("AT+CIPSERVER=1," + (string)portstr).c_str(), "OK", NULL, 1000);
    }
    //sendCommand("AT+CIFSR", "OK", NULL, 1000);
    DBG("Data Mode\r\n");
    state.cmdMode = false;
    if (command_results[0] and command_results[1] and command_results[2]){
        return true;
    }
    else{
        return false;
    }
}

bool ESP8266::close()
{
    wait(0.1f);
    send("+++",3);
    wait(1.0f);
    state.cmdMode = true;
    sendCommand("AT+CIPCLOSE","OK", NULL, 10000);
    return true;
}

bool ESP8266::disconnect()
{
    // if already disconnected, return
    if (!state.associated)
        return true;
    // send command to quit AP
    sendCommand("AT+CWQAP", "OK", NULL, 10000);
    state.associated = false;
    return true;
}

/*
    Assuming Returned data looks like this:
    +CIFSR:STAIP,"192.168.11.2"
    +CIFSR:STAMAC,"18:fe:34:9f:3a:f5"
    grabbing IP from first set of quotation marks
*/
char* ESP8266::getIPAddress()
{
    char result[30] = {0};
    int check = 0;
    check = sendCommand("AT+CIFSR", NULL, result, 1000);
    //pc.printf("\r\nReceivedInfo for IP Command is: %s\r\n",result);
    ip = ipString;
    if(check) {
        // Success
        string resultString(result);
        uint8_t pos1 = 0, pos2 = 0;
        //uint8_t pos3 = 0, pos4 = 0;
        pos1 = resultString.find("+CIFSR:STAIP");
        pos1 = resultString.find('"',pos1);
        pos2 = resultString.find('"',pos1+1);
        //pos3 = resultString.find('"',pos2+1); //would find mac address
        //pos4 = resultString.find('"',pos3+1);
        strncpy(ipString,resultString.substr(pos1,pos2).c_str(),sizeof(ipString));
        ipString[pos2 - pos1 +1] = 0; // null terminate string correctly.
        INFO("IP: %s",ipString);
        ip = ipString;

    } else {
        // Failure
        ERR("getIPAddress() failed");
        ip = NULL;
    }
    return ip;
}

bool ESP8266::gethostbyname(const char * host, char * ip)
{
    string h = host;
    int nb_digits = 0;

    // no dns needed
    int pos = h.find(".");
    if (pos != string::npos) {
        string sub = h.substr(0, h.find("."));
        nb_digits = atoi(sub.c_str());
    }
    //printf("substrL %s\r\n", sub.c_str());
    if (count(h.begin(), h.end(), '.') == 3 && nb_digits > 0) {
        strcpy(ip, host);
        return true;
    } else {
        // dns needed, not currently available
        ERR("gethostbyname(): DNS Not currently available, only use IP Addresses!");
        return false;
    }
}

void ESP8266::reset()
{
    reset_pin = 0;
    wait_us(20);
    reset_pin = 1;
    //wait(1);
    //reset_pin = !reset_pin
    //send("+++",3);
    wait(1);
    state.cmdMode = true;
    sendCommand("AT", "OK", NULL, 1000);
    sendCommand("AT+RST", "ready", NULL, 10000);
    state.associated = false;

}

bool ESP8266::reboot()
{
    reset();
    return true;
}

void ESP8266::handler_rx(void)
{
    //read characters
    char c;
    while (wifi.readable()) {
        c=wifi.getc();
        buf_ESP8266.queue(c);
        //if (state.cmdMode) pc.printf("%c",c); //debug echo, needs fast serial console to prevent UART overruns
    }
}

void ESP8266::attach_rx(bool callback)
{
    if (!callback) {
        wifi.attach(NULL);
    }
    else {
        wifi.attach(this, &ESP8266::handler_rx);
    }
}

int ESP8266::readable()
{
    return buf_ESP8266.available();
}

int ESP8266::writeable()
{
    return wifi.writeable();
}

char ESP8266::getc()
{
    char c=0;
    while (!buf_ESP8266.available());
    buf_ESP8266.dequeue(&c);
    return c;
}

int ESP8266::putc(char c)
{
    while (!wifi.writeable() || wifi.readable()); //wait for echoed command characters to be read first
    return wifi.putc(c);
}

void ESP8266::flush()
{
    buf_ESP8266.flush();
}

int ESP8266::send(const char * buf, int len)
{
    //TODO: need to add handler for data > 2048B, this is the max packet size of the ESP8266.
    if(len >= 2048){
        WARN("send buffer >= 2048B, need to chunk this up to be less.");    
    }
    const char* bufptr=buf;
    for(int i=0; i<len; i++) {
        putc((int)*bufptr++);
    }
    return len;
}

bool ESP8266::sendCommand(const char * cmd, const char * ACK, char * res, int timeout)
{
    char read;
    size_t found = string::npos;
    string checking = "";
    Timer tmr;
    int result = 0;

    DBG("sendCmd:\t %s",cmd);

    attach_rx(true);

    //We flush the buffer
    while (readable())
        getc();

    if (!ACK || !strcmp(ACK, "NO")) {
        for (int i = 0; i < strlen(cmd); i++) {
            result = (putc(cmd[i]) == cmd[i]) ? result + 1 : result;
            wait(0.005f); // prevents stuck recieve ready (?) need to let echoed character get read first
        }
        putc(13); //CR
        wait(0.005f); // wait for echo
        putc(10); //LF

    } else {
        //We flush the buffer
        while (readable())
            getc();

        tmr.start();
        for (int i = 0; i < strlen(cmd); i++) {
            result = (putc(cmd[i]) == cmd[i]) ? result + 1 : result;
            wait(.005); // wait for echo
        }
        putc(13); //CR
        wait(0.005f); // wait for echo
        putc(10); //LF

        while (1) {
            if (tmr.read_ms() > timeout) {
                //We flush the buffer
                while (readable())
                    getc();

                DBG("check:\t %s", checking.c_str());

                attach_rx(true);
                return -1;
            } else if (readable()) {
                read = getc();
                //printf("%c",read); //debug echo
                if ( read != '\r' && read != '\n') {
                    checking += read;
                    found = checking.find(ACK);
                    if (found != string::npos) {
                        wait(0.01f);

                        //We flush the buffer
                        while (readable())
                            read = getc();
                        //printf("%c",read); //debug echo
                        break;
                    }
                }
            }
        }
        DBG("check: %s", checking.c_str());

        attach_rx(true);
        return result;
    }

    //the user wants the result from the command (ACK == NULL, res != NULL)
    if (res != NULL) {
        int i = 0;
        Timer timeout;
        timeout.start();
        tmr.reset();
        while (1) {
            if (timeout.read() > 2) {
                if (i == 0) {
                    res = NULL;
                    break;
                }
                res[i] = '\0';
                DBG("user str 1: %s", res);

                break;
            } else {
                if (tmr.read_ms() > 300) {
                    res[i] = '\0';
                    DBG("user str: %s", res);

                    break;
                }
                if (readable()) {
                    tmr.start();
                    read = getc();

                    // we drop \r and \n
                    if ( read != '\r' && read != '\n') {
                        res[i++] = read;
                    }
                }
            }
        }
        DBG("user str: %s", res);
    }

    //We flush the buffer
    while (readable())
        getc();

    attach_rx(true);
    DBG("result: %d", result)
    return result;
}