Ben Schueler / Mbed 2 deprecated UDPSocket_Node

this program can by compiled and run on several mbeds in a network. The mbed ID is automatically generated. This program is a small test to see if it works. To test the firmware you will need two ( or more ) mbed modules connected to the same network. Pin p5 should be connected with a push button to 3v3 and a resistor of 10k to ground. If the button is pressed the mbed will broadcast a message on ip 239, 192, 1, 100 on port 50000. All mbeds are listening to this ip address and port so they will pick up this message. If the message says MBED xyz LED ON, led1 will id on. If the message says MBED LED OFF, led1 will be off. It\\\'s that simple. So with one mbed you can turn the other mbeds led on or off.

Dependencies:   EthernetNetIf NTPClient_NetServices mbed

UDPSocketExample.cpp

Committer:
Schueler
Date:
2010-11-24
Revision:
2:ae37f80efd23
Parent:
1:2e2d0b0b57e0
Child:
3:3c33a398189e

File content as of revision 2:ae37f80efd23:

#include "mbed.h"
#include "EthernetNetIf.h"
#include "UDPSocket.h"

Serial pc(USBTX, USBRX);
EthernetNetIf eth;
UDPSocket udp;
DigitalOut led(LED1);
InterruptIn button(p5);
Ticker AliveTicker;

// xxx will be replaced by LSByte of the IP address
//
// Message to let the other know we are alive
char strAlive[15];

char mebed_list[16];

char ButtonPressed = 0;
char SendAlive = 0;
char mbed_id = 0;
char mbed_client = 0;

void Alive()         // ticker routine
{
    SendAlive = 1;
}

void button_pressed()   // irq routine for button
{
    ButtonPressed = 1;
}


void onUDPSocketEvent(UDPSocketEvent e)
{
  switch(e)
  {
  case UDPSOCKET_READABLE: //The only event for now
    char buf[64] = {0};
    Host host;
    while( int len = udp.recvfrom( buf, 63, &host ) )
    {
      if( len <= 0 )
        break;
        
        // should implement a parser...
        // but this will do the trick for the moment
        if ( strncmp ( buf, "MBED", 4 ) == 0 )
        {
            //pc.printf ("message from %d.%d.%d.%d: %s\n", host.getIp()[0], host.getIp()[1], host.getIp()[2], host.getIp()[3], buf );

            mbed_client = 0;
            for ( int i = 5; i < 8; i++ )
            {
                if ( ( buf[i] >= '0' ) & ( buf[i] <= '9' ) ) { mbed_client *=10; mbed_client += ( buf[i] - '0' ); }
            }
            if ( strstr (buf, "ALIVE") != NULL )
            {
                pc.printf ("MBED %d is alive\n\r", mbed_client );
            }
            if ( strstr (buf, "LED") != NULL )
            {
                pc.printf ("Message for MBED %d\n\r", mbed_client );
                if ( strstr (buf, "ON")  != NULL ) { led = 1; }
                if ( strstr (buf, "OFF") != NULL ) { led = 0; }
            }
        }
    }
    break;
  }
}

int main() {
  char pos = 0;
  pc.baud(115200);
  pc.printf("Ethernet...\n");
  EthernetErr ethErr = eth.setup();
  if(ethErr)
  {
    pc.printf("Error %d in setup.\n", ethErr);
    return -1;
  }
  pc.printf("  OK\n\r");

  IpAddr ethIp = eth.getIp();
  mbed_id = ethIp[3];
  sprintf( strAlive, "MBED %d ALIVE\0", mbed_id );

  pc.printf( "%s\n\r", strAlive );
  // set Alive Broadcast to 10 seconds
  AliveTicker.attach(&Alive, 10);  
  Host multicast(IpAddr(239, 192, 1, 100), 50000, NULL); //Join multicast group on port 50000
 
  udp.setOnEvent(&onUDPSocketEvent);
  
  udp.bind(multicast);

  udp.sendto( strAlive, strlen(strAlive), &multicast );
  
  button.rise(&button_pressed);
  while(true)
  {
    Net::poll();
    if ( SendAlive == 1 ) { udp.sendto( strAlive, strlen(strAlive), &multicast ); SendAlive = 0; }    // Send Alive Signal
    
    if( ButtonPressed != 0 )
    {
      char strout[20];
      pos = !pos;
      if ( pos == 0 ) sprintf( strout, "MBED %d LED OFF\0", mbed_client ); else sprintf( strout, "MBED %d LED ON\0", mbed_client );
      udp.sendto( strout, strlen(strout), &multicast );
      //pc.printf("%s\n", str);
      ButtonPressed = 0;
    }
  }

  
}