arduino - 如何让 2 个 Arduinos 通过以太网通信变量？

Question

所以事情是这样的，我有 2 个 arduino mega，两个都有w5100(wiznet)盾牌。一个有光传感器，我需要另一个能够从另一个位置获取光传感器的值。我已经搜索过，但找不到这样的东西。我有它client.Println();的价值，但我不确定如何获取，而不是存储它。

请帮忙，乔伊

Answer 1

http://arduino.cc/en/Reference/EthernetServer提供的代码几乎可以准确地告诉您您需要什么。此处复制/改编的亮点。

首先是“接收端”：

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

// network configuration.  
// gateway and subnet are optional.

 // the media access control (ethernet hardware) address for the shield:
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };  

//the IP address for the shield:
byte ip[] = { 10, 0, 0, 177 };    

// the router's gateway address:
byte gateway[] = { 10, 0, 0, 1 };

// the subnet:
byte subnet[] = { 255, 255, 0, 0 };

// telnet defaults to port 23
EthernetServer server = EthernetServer(23);

void setup()
{
  // initialize the ethernet device
  Ethernet.begin(mac, ip, gateway, subnet);

  // start listening for clients
  server.begin();
}

void loop()
{
  // if an incoming client connects, there will be bytes available to read:
  char incoming[100];
  EthernetClient client = server.available();
  if (client == true) {
    // read bytes from the incoming client and write them back
    // to any clients connected to the server:
    int ii = 0;
    while ((c = client.read()) != '\n') 
    {
      incoming[ii++] = c;
    }
    // the variable incoming[] now contains the most recent value sent
    // so you can do something with it  
  }
}

现在是“发送部分”（在作为数据源的 Arduino 上运行的草图）：

#include <SPI.h>
#include <Ethernet.h>
// inspired by/copied from http://arduino.cc/en/Tutorial/TelnetClient

// Enter a MAC address and IP address for your controller below:
// The IP address will be dependent on your local network:
byte mac[] = { 0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
IPAddress ip(192,168,1,176);  // this is the data source card IP address

// the IP address of the server you're connecting to:
IPAddress server(192,168,1,177);

// Initialize the Ethernet client library
// with the IP address and port of the server 
// that you want to connect to (port 23 is default for telnet;
EthernetClient client;
int port = 23;  // telnet default port

char myVar[100]; // contains string with variable to transmit

void setup() {
  // start the Ethernet connection:
  Ethernet.begin(mac, ip);
 // Open serial communications and wait for port to open:
  Serial.begin(9600);
   while (!Serial) {
    ; // wait for serial port to connect. Needed for Leonardo only
  }

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

  // if you get a connection, report back via serial:
  if (client.connect(server, port)) {
    Serial.println("connected");
  } 
  else {
    // if you didn't get a connection to the server:
    Serial.println("connection failed");
  }
}

void loop()
{
  // if there are incoming bytes available 
  // from the server, read them and print them:
  // the server code above doesn't send anything…
  // but if it did, this is where you would echo it
  int ii;
  if (client.available()) {
    char c = client.read();
    Serial.print("***Server says:***\n");
    Serial.print(c);
  }

  // assume your variable myVar will have a valid string in it...
  strcpy(myVar, "123.456\n");
  // tell the serial port what you are sending:
  Serial.print("sending variable: ");
  Serial.print(myVar);
  for(ii = 0; ii < strlen(myVar); ii++) {
    if (client.connected()) {
      client.print(myVar[ii]); 
    }
  }

  // if the server's disconnected, stop the client:
  if (!client.connected()) {
    Serial.println();
    Serial.println("disconnecting.");
    client.stop();
    // do nothing:
    while(true);
  }
  // add appropriate delay here before sending next data element
}

我没有两个带以太网屏蔽的 Arduino，所以我不得不根据我所知道/可以查找的内容将其拼凑起来。让我知道你是怎么做的！

Answer 2

给尝试这个的人的一些提示：

首先，在我写这篇文章的时候，上面的代码不适用于 1.0.5 以上的任何版本（1.0.5r2 可以正常工作）。

发件人还具有以下内容：

// the IP address of the server you're connecting to:
IPAddress server(192.168,1,177);

应该是（逗号，不是空格）：

// the IP address of the server you're connecting to:
IPAddress server(192,168,1,177);

到目前为止只是我的发现！:)