Revision 0:a94222cedd2e, committed 2015-05-01

Comitter:

adhithyan15

Date:

Fri May 01 14:46:00 2015 +0000

Commit message:

Initial Commit;

Changed in this revision

diff -r 000000000000 -r a94222cedd2e esp8266.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/esp8266.cpp	Fri May 01 14:46:00 2015 +0000
@@ -0,0 +1,302 @@
+#include "esp8266.h"
+#include <algorithm>
+#include <cctype>
+
+// This file implements the methods described in the esp8266 header file
+// Copyright: Adhithya Rajasekaran
+// License: MIT License
+
+/* General Note About ESP8266
+
+   ESP8266 is controlled by using AT commands sent via Serial. Most of the API
+   is implemented with AT commands. You can find the list of all AT commands at
+   https://nurdspace.nl/ESP8266 
+
+*/
+
+ESP8266::ESP8266(MODSERIAL *input, char* inputSSID, char* inputPassword){
+    /*
+     Inputs:
+         1. MODSERIAL* input - Pass in a reference to a MODSERIAL object. This MODSERIAL object should be connected to the
+            ESP8266 module's pins 3 and 4. MODSERIAL is used instead of regular serial because it has buffering capability.
+         2. char* inputSSID - Pass in a reference to a character array consisting of the SSID of the wireless network you
+            want to connect to. Currently the library assumes that you are passing in the correct SSID and won't do any error
+            checking. 
+         3. char* inputPassword - Pass in a reference to a character array consisting of the password/shared key of the wireless network you
+            want to connect to. Currently the library assumes that you are passing in the correct password and won't do any error
+            checking. 
+         
+     TODO:
+        1. Error checking of SSIDs by calling listOfAccessPoints() method and checking if the inputSSID is in the output of
+           listOfAccessPoints() method. 
+        2. Error checking of passwords by trying to actually connect the access point  
+    */
+    wifi = input;
+    wifi->baud(115200); // This is the baud rate required to communicate the ESP8266 chip
+    connection_successful = false;
+    if(wiredCorrectly()){
+      //connection_successful = true;
+        if(joinAccessPoint(inputSSID,inputPassword)){
+             getMyIP();
+             string error = "ERROR";
+             if(ip != error){
+                connection_successful = true;      
+             }   
+        }
+    }
+}
+
+string removeSpaces(string input)
+{
+  input.erase(std::remove(input.begin(),input.end(),'\r'),input.end());
+  input.erase(std::remove(input.begin(),input.end(),'\n'),input.end());
+  return input;
+}
+
+bool ESP8266::wiredCorrectly(){
+    // This method checks if the ESP8266 module is wired correctly. 
+    
+    wifi->printf("AT\r\n");
+    wait(2);
+    char buf[20];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+   size_t found = actual_output.find("OK");
+   if (found!=std::string::npos){
+     if(reset() == true){
+       setMode(3);
+       return true;  
+     }else{
+       return false;   
+     }
+   }else{
+     return false;    
+   }
+}
+
+bool ESP8266::reset(){
+   // This method resets the settings inside the ESP8266 chip
+   
+    wifi->printf("AT+RST\r\n");
+    wait(2);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+   size_t found = actual_output.find("rst");
+   if (found!=std::string::npos){
+    return true;
+   }else{
+    return false;   
+   }
+}
+
+char* ESP8266::firmwareVersion(){
+    // Incomplete Method. Just use for firmware debugging purposes
+    wifi->printf("AT+GMR\r\n");
+    wait(2);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+   const char* output = actual_output.c_str();
+   return (char*) output;
+}
+
+void ESP8266::setMode(int val){
+    // ESP8266 is set to mode 3 which will allow it to act
+    // both as a client and server.
+    wifi->printf("AT+CWMODE=3\r\n");
+    wait(2);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+}
+
+bool ESP8266::checkConnection(){
+    return connection_successful;   
+}
+
+bool ESP8266::gotAnIPAddress(){
+    wifi->printf("AT+CIFSR\r\n");
+    wait(2);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+   size_t found = actual_output.find("ERROR");
+   if (found!=std::string::npos){
+    return false;
+   }else{
+    return true;   
+   }
+}
+
+
+bool ESP8266::joinAccessPoint(char *inputSSID, char *inputPassword){
+    // This method establishes connection with the requested access point
+    // All authentication methods are supported (WEP, WPA)
+    wifi->printf("AT+CWJAP=\"%s\",\"%s\"\r\n",inputSSID,inputPassword);
+    wait(7);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   //delete[] buf;
+   printf("\n");
+   if(gotAnIPAddress() == true){
+     return true;   
+   }else{
+     return false;   
+   }
+}
+
+string ESP8266::getMyIP(){
+    // Fetches the assigned IP address of the module
+    wifi->printf("AT+CIFSR\r\n");
+    wait(2);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(actual_output.c_str());
+   string s = actual_output;
+   //delete[] buf;
+   s.erase( remove_if( s.begin(), s.end(),std::isspace ), s.end() );
+   string ip_address = s.substr(8,s.length());
+   string error = "ERROR";
+   if(ip_address == error){
+     ip = error;
+   }else{
+     ip = ip_address;
+   }
+   return ip;
+}
+
+bool ESP8266::checkSSID(string inputSSID){
+    // This method checks the presence of the input SSID
+    // with all the SSIDs that the ESP8266 chip detects
+    wifi->printf("AT+CWLAP\r\n");
+    wait(10);
+    char buf[2000];
+    int counter = 0;
+    while(1){
+     if(wifi->readable()){
+        buf[counter] = wifi->getc();
+        counter = counter + 1;
+     }else{
+        wait(2);
+        if(!wifi->readable()){
+          break;   
+        }   
+     }   
+    }
+   string test(buf);
+   string actual_output = test.substr(0,counter);
+   printf(inputSSID.c_str());
+   printf(actual_output.c_str());
+   wait(5);
+   size_t found = actual_output.find(inputSSID);
+   printf("I am here");
+   if (found!=std::string::npos){
+     return false;
+   }else{
+     return true;   
+   }
+   //delete[] buf;
+}
\ No newline at end of file

diff -r 000000000000 -r a94222cedd2e esp8266.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/esp8266.h	Fri May 01 14:46:00 2015 +0000
@@ -0,0 +1,36 @@
+/* A simple library for interfacing with ESP8266 Wifi Module
+   The API has been designed to very user friendly. The current
+   version had to be developed in a very short amount of time. So
+   its error handling capabilities are very limited. So please feel
+   free to fork the project and contribute. 
+   
+   Copyright: Adhithya Rajasekaran
+   Released Under: MIT License
+*/
+
+#include "mbed.h"
+#include <string>
+#include "MODSERIAL.h"
+
+class ESP8266{
+ private:  
+   char *ssid;
+   char *password;
+   string ip;
+   bool connection_successful;
+   MODSERIAL *wifi;
+   char* sendCmd(char* cmd);
+   char* firmwareVersion();
+   bool reset();
+   void setMode(int modeVal);
+   bool wiredCorrectly();
+   bool joinAccessPoint(char *inputSSID, char *inputPassword);
+   bool gotAnIPAddress();
+   bool checkSSID(string inputSSID);
+ public:
+   ESP8266(MODSERIAL *input, char* inputSSID, char* inputPassword);
+   bool checkConnection();
+   string listAccessPoints();
+   bool disconnect();
+   string getMyIP();
+};
\ No newline at end of file