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Atmel website says that the chip WINC1500 supports WiFi-Direct. The WiFi101 software library that comes with Arduino IDE has no API that indicate WiFi-Direct support. The first step is to add WiFi-Direct functionality into WiFi101 library.

I forked the WiFi101 on github and soon discovered that the file WiFi.cpp is the best place to implement the additional APIs needed to connect to WiFi-Direct. I added the follwing APIs:

 /*

* Start Wifi as P2P device. P2P is also known as Wi-Fi Direct.

*

* param name: Set your device name which will be shown in the peer device.

* param channel: Wifi channel to use. Valid values are 0, 5 and 10.	*

*/

uint8_t beginP2P(const char *name);


uint8_t beginP2P(const char *name, uint8_t channel);

This follows the same design pattern as the other APIs for configuring WiFi in station mode or Access Point mode.

There is already an infrastructure in place to handle callbacks. I reused the same logic and implemented the WiFi-Direct API. I added a new example to demonstrate how to connect to WiFi-Direct, it is:

#include <WiFi101.h>

char name[] = "wifi101-p2p"; // P2P device name

void setup() {

  // attempt to connect to Wifi-Direct:
  if ( WiFi.beginP2P(name) != WL_CONNECTED) {
    // don't continue:
    while (true);
  }

  // you're connected now, so print out the data:
  printCurrentNet();
  printWifiData();
}

void loop() {
  // communicate normally
}

When I coded everything and ran it, it did not connect. On investigation it turned out that I cannot use channel values between 1 to 12 as is the case for Access Point mode. The only allowed channel values are 0, 5 and 10. On using the correct channels it worked like a charm. Please see the connection dialog from Android below: