为什么我不能使用 android 和 esp8266 关闭 arduino 上的 LED

why cant i turn off led's on arduino using android and esp8266

我已经尝试制作一个 android 应用程序来使用 arduino 打开或关闭 LED。

esp8266 esp-01 提供接入点。

但我无法关闭 LED 的使用总是有一些错误

另外,当我在串行监视器中看到数据时,它部分是乱码

我已经从 allaboutee 获取了代码。com/2015/01/20/esp8266-android-application-for-arduino-pin-control/

但它被我修改了,因为它在 2 和 3 针上对我不起作用

我用过arduino uno

The circuit diagram is like this

arduino的代码如下:

#include <SoftwareSerial.h>

#define DEBUG true

SoftwareSerial esp8266(10,11); // make RX Arduino line is pin 2, make TX Arduino line is pin 3.
                             // This means that you need to connect the TX line from the esp to the Arduino's pin 2
                             // and the RX line from the esp to the Arduino's pin 3
void setup()
{
  Serial.begin(115200);
  esp8266.begin(115200); // your esp's baud rate might be different

  pinMode(2,OUTPUT);
  digitalWrite(2,LOW);

  pinMode(3,OUTPUT);
  digitalWrite(3,LOW);

  pinMode(4,OUTPUT);
  digitalWrite(4,LOW);

  pinMode(6,OUTPUT);
  digitalWrite(6,LOW);

  sendCommand("AT+RST\r\n",2000,DEBUG); // reset module
  sendCommand("AT+CWMODE=2\r\n",1000,DEBUG); // configure as access point
  delay(1000);
  sendCommand("AT+CIFSR\r\n",1000,DEBUG); // get ip address
  sendCommand("AT+CIPMUX=1\r\n",1000,DEBUG); // configure for multiple connections
  sendCommand("AT+CIPSERVER=1,80\r\n",1000,DEBUG); // turn on server on port 80

  Serial.println("Server Ready");
}

void loop()
{
  if(esp8266.available()) // check if the esp is sending a message 
  {


    if(esp8266.find("+IPD,"))
    {
     delay(1000); // wait for the serial buffer to fill up (read all the serial data)
     // get the connection id so that we can then disconnect
     int connectionId = esp8266.read()-48; // subtract 48 because the read() function returns 
                                           // the ASCII decimal value and 0 (the first decimal number) starts at 48

     esp8266.find("pin="); // advance cursor to "pin="

     int pinNumber = (esp8266.read()-48); // get first number i.e. if the pin 13 then the 1st number is 1
     int secondNumber = (esp8266.read()-48);
     if(secondNumber>=0 && secondNumber<=9)
     {
      pinNumber*=10;
      pinNumber +=secondNumber; // get second number, i.e. if the pin number is 13 then the 2nd number is 3, then add to the first number
     }

     digitalWrite(pinNumber, !digitalRead(pinNumber)); // toggle pin    

     // build string that is send back to device that is requesting pin toggle
     String content;
     content = "Pin ";
     content += pinNumber;
     content += " is ";

     if(digitalRead(pinNumber))
     {
       content += "ON";
     }
     else
     {
       content += "OFF";
     }

     sendHTTPResponse(connectionId,content);

     // make close command
     String closeCommand = "AT+CIPCLOSE="; 
     closeCommand+=connectionId; // append connection id
     closeCommand+="\r\n";

     sendCommand(closeCommand,1000,DEBUG); // close connection
    }
  }
}

/*
* Name: sendData
* Description: Function used to send data to ESP8266.
* Params: command - the data/command to send; timeout - the time to wait for a response; debug - print to Serial window?(true = yes, false = no)
* Returns: The response from the esp8266 (if there is a reponse)
*/
String sendData(String command, const int timeout, boolean debug)
{
    String response = "";

    int dataSize = command.length();
    char data[dataSize];
    command.toCharArray(data,dataSize);

    esp8266.write(data,dataSize); // send the read character to the esp8266
    if(debug)
    {
      Serial.println("\r\n====== HTTP Response From Arduino ======");
      Serial.write(data,dataSize);
      Serial.println("\r\n========================================");
    }

    long int time = millis();

    while( (time+timeout) > millis())
    {
      while(esp8266.available())
      {

        // The esp has data so display its output to the serial window 
        char c = esp8266.read(); // read the next character.
        response+=c;
      }  
    }

    if(debug)
    {
      Serial.print(response);
    }

    return response;
}

/*
* Name: sendHTTPResponse
* Description: Function that sends HTTP 200, HTML UTF-8 response
*/
void sendHTTPResponse(int connectionId, String content)
{

     // build HTTP response
     String httpResponse;
     String httpHeader;
     // HTTP Header
     httpHeader = "HTTP/1.1 200 OK\r\nContent-Type: text/html; charset=UTF-8\r\n"; 
     httpHeader += "Content-Length: ";
     httpHeader += content.length();
     httpHeader += "\r\n";
     httpHeader +="Connection: close\r\n\r\n";
     httpResponse = httpHeader + content; // There is a bug in this code: the last character of "content" is not sent, I cheated by adding this extra space
     sendCIPData(connectionId,httpResponse);
}

/*
* Name: sendCIPDATA
* Description: sends a CIPSEND=<connectionId>,<data> command
*
*/
void sendCIPData(int connectionId, String data)
{
   String cipSend = "AT+CIPSEND=";
   cipSend += connectionId;
   cipSend += ",";
   cipSend +=data.length();
   cipSend +="\r\n";
   sendCommand(cipSend,1000,DEBUG);
   sendData(data,1000,DEBUG);
}

/*
* Name: sendCommand
* Description: Function used to send data to ESP8266.
* Params: command - the data/command to send; timeout - the time to wait for a response; debug - print to Serial window?(true = yes, false = no)
* Returns: The response from the esp8266 (if there is a reponse)
*/
String sendCommand(String command, const int timeout, boolean debug)
{
    String response = "";

    esp8266.print(command); // send the read character to the esp8266

    long int time = millis();

    while( (time+timeout) > millis())
    {
      while(esp8266.available())
      {

        // The esp has data so display its output to the serial window 
        char c = esp8266.read(); // read the next character.
        response+=c;
      }  
    }

    if(debug)
    {
      Serial.print(response);
    }

    return response;
}

android的代码如下:

主要活动:

package com.example.autohome;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.AsyncTask;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;

import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URI;
import java.net.URISyntaxException;

public class MainActivity extends Activity implements View.OnClickListener {

    public final static String PREF_IP = "PREF_IP_ADDRESS";
    public final static String PREF_PORT = "PREF_PORT_NUMBER";
    // declare buttons and text inputs
    private Button buttonPin11,buttonPin12,buttonPin13;
    private EditText editTextIPAddress, editTextPortNumber;
    // shared preferences objects used to save the IP address and port so that the user doesn't have to
    // type them next time he/she opens the app.
    SharedPreferences.Editor editor;
    SharedPreferences sharedPreferences;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        sharedPreferences = getSharedPreferences("HTTP_HELPER_PREFS",Context.MODE_PRIVATE);
        editor = sharedPreferences.edit();

        // assign buttons
        buttonPin11 = (Button)findViewById(R.id.buttonPin11);
        buttonPin12 = (Button)findViewById(R.id.buttonPin12);
        buttonPin13 = (Button)findViewById(R.id.buttonPin13);

        // assign text inputs
        editTextIPAddress = (EditText)findViewById(R.id.editTextIPAddress);
        editTextPortNumber = (EditText)findViewById(R.id.editTextPortNumber);

        // set button listener (this class)
        buttonPin11.setOnClickListener(this);
        buttonPin12.setOnClickListener(this);
        buttonPin13.setOnClickListener(this);

        // get the IP address and port number from the last time the user used the app,
        // put an empty string "" is this is the first time.
        editTextIPAddress.setText(sharedPreferences.getString(PREF_IP,""));
        editTextPortNumber.setText(sharedPreferences.getString(PREF_PORT,""));
    }


    @Override
    public void onClick(View view) {

        // get the pin number
        String parameterValue = "";
        // get the ip address
        String ipAddress = editTextIPAddress.getText().toString().trim();
        // get the port number
        String portNumber = editTextPortNumber.getText().toString().trim();


        // save the IP address and port for the next time the app is used
        editor.putString(PREF_IP,ipAddress); // set the ip address value to save
        editor.putString(PREF_PORT,portNumber); // set the port number to save
        editor.commit(); // save the IP and PORT

        // get the pin number from the button that was clicked
        if(view.getId()==buttonPin11.getId())
        {
            parameterValue = "2";
        }
        else if(view.getId()==buttonPin12.getId())
        {
            parameterValue = "3";
        }
        else
        {
            parameterValue = "4";
        }



        // execute HTTP request
        if(ipAddress.length()>0 && portNumber.length()>0) {
            new HttpRequestAsyncTask(
                    view.getContext(), parameterValue, ipAddress, portNumber, "pin"
            ).execute();
        }
    }

    /**
     * Description: Send an HTTP Get request to a specified ip address and port.
     * Also send a parameter "parameterName" with the value of "parameterValue".
     * @param parameterValue the pin number to toggle
     * @param ipAddress the ip address to send the request to
     * @param portNumber the port number of the ip address
     * @param parameterName
     * @return The ip address' reply text, or an ERROR message is it fails to receive one
     */
    public String sendRequest(String parameterValue, String ipAddress, String portNumber, String parameterName) {
        String serverResponse = "ERROR";

        try {

            HttpClient httpclient = new DefaultHttpClient(); // create an HTTP client
            // define the URL e.g. http://myIpaddress:myport/?pin=13 (to toggle pin 13 for example)
            URI website = new URI("http://"+ipAddress+":"+portNumber+"/?"+parameterName+"="+parameterValue);
            HttpGet getRequest = new HttpGet(); // create an HTTP GET object
            getRequest.setURI(website); // set the URL of the GET request
            HttpResponse response = httpclient.execute(getRequest); // execute the request
            // get the ip address server's reply
            InputStream content = null;
            content = response.getEntity().getContent();
            BufferedReader in = new BufferedReader(new InputStreamReader(
                    content
            ));
            serverResponse = in.readLine();
            // Close the connection
            content.close();
        } catch (ClientProtocolException e) {
            // HTTP error
            serverResponse = e.getMessage();
            e.printStackTrace();
        } catch (IOException e) {
            // IO error
            serverResponse = e.getMessage();
            e.printStackTrace();
        } catch (URISyntaxException e) {
            // URL syntax error
            serverResponse = e.getMessage();
            e.printStackTrace();
        }
        // return the server's reply/response text
        return serverResponse;
    }


    /**
     * An AsyncTask is needed to execute HTTP requests in the background so that they do not
     * block the user interface.
     */
    private class HttpRequestAsyncTask extends AsyncTask<Void, Void, Void> {

        // declare variables needed
        private String requestReply,ipAddress, portNumber;
        private Context context;
        private AlertDialog alertDialog;
        private String parameter;
        private String parameterValue;

        /**
         * Description: The asyncTask class constructor. Assigns the values used in its other methods.
         * @param context the application context, needed to create the dialog
         * @param parameterValue the pin number to toggle
         * @param ipAddress the ip address to send the request to
         * @param portNumber the port number of the ip address
         */
        public HttpRequestAsyncTask(Context context, String parameterValue, String ipAddress, String portNumber, String parameter)
        {
            this.context = context;

            alertDialog = new AlertDialog.Builder(this.context)
                    .setTitle("HTTP Response From IP Address:")
                    .setCancelable(true)
                    .create();

            this.ipAddress = ipAddress;
            this.parameterValue = parameterValue;
            this.portNumber = portNumber;
            this.parameter = parameter;
        }

        /**
         * Name: doInBackground
         * Description: Sends the request to the ip address
         * @param voids
         * @return
         */
        @Override
        protected Void doInBackground(Void... voids) {
            alertDialog.setMessage("Data sent, waiting for reply from server...");
            if(!alertDialog.isShowing())
            {
                alertDialog.show();
            }
            requestReply = sendRequest(parameterValue,ipAddress,portNumber, parameter);
            return null;
        }

        /**
         * Name: onPostExecute
         * Description: This function is executed after the HTTP request returns from the ip address.
         * The function sets the dialog's message with the reply text from the server and display the dialog
         * if it's not displayed already (in case it was closed by accident);
         * @param aVoid void parameter
         */
        @Override
        protected void onPostExecute(Void aVoid) {
            alertDialog.setMessage(requestReply);
            if(!alertDialog.isShowing())
            {
                alertDialog.show(); // show dialog
            }
        }

        /**
         * Name: onPreExecute
         * Description: This function is executed before the HTTP request is sent to ip address.
         * The function will set the dialog's message and display the dialog.
         */
        @Override
        protected void onPreExecute() {
            alertDialog.setMessage("Sending data to server, please wait...");
            if(!alertDialog.isShowing())
            {
                alertDialog.show();
            }
        }

    }
}

布局文件:

<?xml version="1.0" encoding="utf-8"?>
<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
     >

    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:orientation="vertical">


        <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:text="IP Address:"
        android:id="@+id/textView" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="e.g. 192.168.0.10"
        android:id="@+id/editTextIPAddress" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Port Number:"
        android:id="@+id/textView2" />

    <EditText
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:inputType="number"
        android:ems="10"
        android:hint="e.g. 80"
        android:id="@+id/editTextPortNumber" />

        <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Pin 11"
        android:id="@+id/buttonPin11" />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Pin 12"
        android:id="@+id/buttonPin12" />

    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Pin 13"
        android:id="@+id/buttonPin13" />
    </LinearLayout>

</ScrollView>

These are the serial monitor images.

当响应不是乱码时程序运行。当它的乱码出现问题时

post如有遗漏请见谅。 对于 post 中的任何错误,我也深表歉意,因为这是我的第一个

你越来越乱了,因为 Arduino 无法为 ESP8266 提供足够的电流,尤其是当它是 transmitting/receiving 数据时。 ESP8266 模块可能会尝试吸收约 320mA 的峰值电流,而 Arduino 3.3V 稳压输出额定值高达 50mA,因此您必须使用外接电源。

我用 ESP8266 在原厂固件上的实验让我觉得通信波特率 115200 工作不稳定。改用 57600,这绝对有效。