Ethernet Library messes up code

Other Hardware General Electronics
1

Hi,

I'm having a problem with the ethernet library. I'm building a device that sends UDP packets every time a button is pressed. But when I start the ethernet library my code doesn't execute like it should.

Here's a slimmed down version of the code

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

byte mac[] = {0xDE, 0xAD, 0xBE, 0xEF, 0xFE, 0xED };
byte ip[] = { 2, 9, 200, 175 };  // ip adres arduino
unsigned int localPort = 52193;      // local port to listen o
IPAddress destinationIP =(2,9,200,176); // ipadress chamsys
unsigned int destinationPort = 6553; // poort van chamsys
EthernetUDP Udp;

void setup()
{
  Ethernet.begin(mac, ip);  //When this is included, the commands aren't executed in the right way (1,24,36) ...
  Udp.begin(localPort);
  Serial.begin(9600);
  Serial.println("thunderbirds are go !!");
}

void loop()
{     
    if(digitalRead(47) == HIGH && digitalRead(30) == HIGH){sendCommand("0G");} 
    if(digitalRead(47) == HIGH && digitalRead(32) == HIGH){sendCommand("1G");} 
    if(digitalRead(47) == HIGH && digitalRead(34) == HIGH){sendCommand("2G");} 
    if(digitalRead(47) == HIGH && digitalRead(36) == HIGH){sendCommand("3G");} 
    if(digitalRead(47) == HIGH && digitalRead(38) == HIGH){sendCommand("4G");} 
    if(digitalRead(47) == HIGH && digitalRead(40) == HIGH){sendCommand("5G");} 
    if(digitalRead(47) == HIGH && digitalRead(42) == HIGH){sendCommand("6G");} 
    if(digitalRead(47) == HIGH && digitalRead(44) == HIGH){sendCommand("7G");} 
    if(digitalRead(47) == HIGH && digitalRead(46) == HIGH){sendCommand("8G");} 
    //...
    if(digitalRead(22) == HIGH && digitalRead(52) == HIGH){sendCommand("95G");} 
}


void sendCommand(char *command)
{
  Serial.println();
  Serial.print(command);
  Serial.print(" is send");
  Serial.println();
  //send UDP packet ...
}

When I press the first button I get this output

But when I comment out Ethernet.begin I get this output.

Can someone please explain me what's the cause of this (and a possible solution?)

The board is an Arduino Mega2560 with a R3 Ethernet shield

Thanks in advance :slight_smile:

Dieter

2

Remember that on the Arduino MEGA the SPI interface that is used to talk to the Etherenet board uses pins 50-52. Don't try to use those pins for I/O.