Anyone used the w5100 INT to signal the arduino of data?

Projects Networking, Protocols, and Devices
1

Has anyone used the INT signal (digital pin 2) of the w5100 shield to signal the arduino that a connection might be ready? I'm wondering if I can put the thing to sleep, and have an incoming connection wake the thing up.

Currently, I have :

void wakeMeUp() {
awakened_by_ethernet++;
}

And then in the loop :

attachInterrupt(0,wakeMeUp,CHANGE);
delay(100);
set_sleep_mode(SLEEP_MODE_IDLE);
// set_sleep_mode(SLEEP_MODE_PWR_DOWN);
sleep_enable();
sleep_mode();
sleep_disable();
detachInterrupt(0);
Serial.print("interrupted_by_ethernet = ");
Serial.println(awakened_by_ethernet);

This is just to see if I can get this piece to work. I have another interrupt already working on incoming digital pins, but I'd like to also wake up based on incoming network connections to probe the passive sensors, too.

I have soldered the INT connection together on the w5100 already, but I get no interrupt. I've also tried with attachInterrupt(2,...);

Thanks,
Joe

2

I am wondering if I have to do some initialization to the w5100 shield. I tried variations of the code, but to no avail. The EthernetShield page (http://arduino.cc/en/Main/ArduinoEthernetShield) states "The solder jumper marked "INT" can be connected to allow the Arduino board to receive interrupt-driven notification of events from the W5100, but this is not supported by the Ethernet library."

Does that mean I have to rewrite the library, or does it mean I have to code around the library (e.g. not using the "attachInterrupt" functions)? Or is there another way?

3

In plain C I did it that way

sei(); //enable external interrupts;
DDRE &= ~(1<<4);  // set the pin 4 onPORT E on input
EIMSK = 0b00010000; //Set the External Interrupt Mask Register
SPI_Write (IMR,0xFF); //enable all interrupts in w5100

Perhaps what you are missing is setting that Interrupt Mask Register (IMR) setup.