c++ - GET HTTP 请求 (Arduino)

Question

我正在尝试从 Arduino 向我的服务器发送一些 http 请求。

我的代码可以上传一次，但是第一次上传后就断开了。

知道如何修改我的代码以便 Arduino 每 2-3 秒发送一次 http 请求吗？

这是我的代码:

#include <SPI.h>
#include <Ethernet.h>

int counter = 0;

byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress server(xxx, xx, xx, xx); 
IPAddress ip(192, 168, 1, 1);
EthernetClient client;

void setup() { //connect to server
  Serial.begin(9600);

  if (Ethernet.begin(mac) == 0) {
    Serial.println("Failed to configure Ethernet using DHCP");
    Ethernet.begin(mac, ip);
  }

  // give the Ethernet shield a second to initialize:
  delay(1000);
  Serial.println("connecting...");
  connect();
}

void loop()
{

    send(counter);
    delay(1000);
  // if there are incoming bytes available 
  // from the server, read them and print them:
  if (client.available()) {
    char c = client.read();
    Serial.print(c);
  }

  // if the server's disconnected, stop the client:
  if (!client.connected()) {
    Serial.println();
    Serial.println("disconnecting.");
    client.stop();
    // do nothing forevermore:
    while(true); 
  }
  counter++;
}

void connect(){
// if you get a connection, report back via serial:
  client.connect(server, 80);
  Serial.println("CONNECTED");
  delay(1000);
}

void send(int value){
      // Make a HTTP request:
    client.print("GET /arduino.php?rom=D201");
    client.print("&count=");
    client.print(value);
    client.println(" HTTP/1.0");
    client.println("Host: 158.36.70.36");
    client.println("Connection: close");
    client.println();
    Serial.print("Sending value");
    Serial.println(value);
}

Answer 1

此 Web 客户端草图已经过测试并且可以完美运行。

#include <SPI.h>
#include <Ethernet.h>

// this must be unique
byte mac[] = {  0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };

// change to your network settings
IPAddress ip(192,168,2,2);
IPAddress gateway(192, 168, 2, 1);
IPAddress subnet(255, 255, 255, 0);

// change to your server
IPAddress server(74,125,227,16); // Google

//Change to your domain name for virtual servers
char serverName[] = "www.google.com";
// If no domain name, use the ip address above
// char serverName[] = "74.125.227.16";

// change to your server's port
int serverPort = 80;

EthernetClient client;
int totalCount = 0;
char pageAdd[64];

// set this to the number of milliseconds delay
// this is 30 seconds
#define delayMillis 30000UL

unsigned long thisMillis = 0;
unsigned long lastMillis = 0;

void setup() {
  Serial.begin(9600);

  // disable SD SPI
  pinMode(4,OUTPUT);
  digitalWrite(4,HIGH);

  // Start ethernet
  Serial.println(F("Starting ethernet..."));
  Ethernet.begin(mac, ip, gateway, gateway, subnet);

  // If using dhcp, comment out the line above 
  // and uncomment the next 2 lines

  // if(!Ethernet.begin(mac)) Serial.println(F("failed"));
  // else Serial.println(F("ok"));

  Serial.println(Ethernet.localIP());

  delay(2000);
  Serial.println(F("Ready"));
}

void loop()
{
  thisMillis = millis();

  if(thisMillis - lastMillis > delayMillis)
  {
    lastMillis = thisMillis;

    // Modify next line to load different page
    // or pass values to server
    sprintf(pageAdd,"/",totalCount);

    // sprintf(pageAdd,"/arduino.php?test=%u",totalCount);

    if(!getPage(server,serverPort,pageAdd)) Serial.print(F("Fail "));
    else Serial.print(F("Pass "));
    totalCount++;
    Serial.println(totalCount,DEC);
  }    
}

byte getPage(IPAddress ipBuf,int thisPort, char *page)
{
  int inChar;
  char outBuf[128];

  Serial.print(F("connecting..."));

  if(client.connect(ipBuf,thisPort) == 1)
  {
    Serial.println(F("connected"));

    sprintf(outBuf,"GET %s HTTP/1.1",page);
    client.println(outBuf);
    sprintf(outBuf,"Host: %s",serverName);
    client.println(outBuf);
    client.println(F("Connection: close\r\n"));
  } 
  else
  {
    Serial.println(F("failed"));
    return 0;
  }

  // connectLoop controls the hardware fail timeout
  int connectLoop = 0;

  while(client.connected())
  {
    while(client.available())
    {
      inChar = client.read();
      Serial.write(inChar);
      // set connectLoop to zero if a packet arrives
      connectLoop = 0;
    }

    connectLoop++;

    // if more than 10000 milliseconds since the last packet
    if(connectLoop > 10000)
    {
      // then close the connection from this end.
      Serial.println();
      Serial.println(F("Timeout"));
      client.stop();
    }
    // this is a delay for the connectLoop timing
    delay(1);
  }

  Serial.println();

  Serial.println(F("disconnecting."));
  // close client end
  client.stop();

  return 1;
}

如果由于某种原因它一直挂起，您可以实现看门狗定时器机制。有关 WDT 的更多信息，请访问 ATmega328P Datasheet.我有一个来 self 的项目的例子:

void watchdogSetup(void) {
cli(); // disable all interrupts
wdt_reset(); // reset the WDT timer
/*
WDTCSR configuration:
WDIE = 1: Interrupt Enable
WDE = 1 :Reset Enable
WDP3 = 0 :For 2000ms Time-out
WDP2 = 1 :For 2000ms Time-out
WDP1 = 1 :For 2000ms Time-out
WDP0 = 1 :For 2000ms Time-out
*/
// Enter Watchdog Configuration mode:
WDTCSR |= (1<<WDCE) | (1<<WDE); //x |= y is the same as  x = x | y
// Set Watchdog settings:
WDTCSR = (1<<WDIE) | (1<<WDE) | (0<<WDP3) | (1<<WDP2) | (1<<WDP1) | (1<<WDP0);
sei();
}

ISR(WDT_vect){// Watchdog timer interrupt.
  digitalWrite(ETHERNET_SHIELD_RESET_PIN, LOW); 
}