File content as of revision 1:3ead502a934a:

#include "mbed.h"
#include "MRF24J40.h"
#include <string>

// RF tranceiver to link with handheld.
MRF24J40 mrf(p11, p12, p13, p14, p21);

// LEDs you can treat these as variables (led2 = 1 will turn led2 on!)
DigitalOut led1(LED1);
DigitalOut led2(LED2);
DigitalOut led3(LED3);
DigitalOut led4(LED4);

// Timer
Timer timer;

// Serial port for showing RX data.
Serial pc(USBTX, USBRX);

// Used for sending and receiving
char txBuffer[128];
char rxBuffer[128];
int rxLen;

//***************** Do not change these methods (please) *****************//

/**
* Receive data from the MRF24J40.
*
* @param data A pointer to a char array to hold the data
* @param maxLength The max amount of data to read.
*/
int rf_receive(char *data, uint8_t maxLength)
{
    uint8_t len = mrf.Receive((uint8_t *)data, maxLength);
    uint8_t header[8]= {1, 8, 0, 0xA1, 0xB2, 0xC3, 0xD4, 0x00};

    if(len > 10) {
        //Remove the header and footer of the message
        for(uint8_t i = 0; i < len-2; i++) {
            if(i<8) {
                //Make sure our header is valid first
                if(data[i] != header[i])
                    return 0;
            } else {
                data[i-8] = data[i];
            }
        }

        //pc.printf("Received: %s length:%d\r\n", data, ((int)len)-10);
    }
    return ((int)len)-10;
}

/**
* Send data to another MRF24J40.
*
* @param data The string to send
* @param maxLength The length of the data to send.
*                  If you are sending a null-terminated string you can pass strlen(data)+1
*/
void rf_send(char *data, uint8_t len)
{
    //We need to prepend the message with a valid ZigBee header
    uint8_t header[8]= {1, 8, 0, 0xA1, 0xB2, 0xC3, 0xD4, 0x00};
    uint8_t *send_buf = (uint8_t *) malloc( sizeof(uint8_t) * (len+8) );

    for(uint8_t i = 0; i < len+8; i++) {
        //prepend the 8-byte header
        send_buf[i] = (i<8) ? header[i] : data[i-8];
    }
    //pc.printf("Sent: %s\r\n", send_buf+8);

    mrf.Send(send_buf, len+8);
    free(send_buf);
}


//***************** You can start coding here *****************//

int main (void)
{
    //Set the channel of the slave
    uint8_t channel = 15;
    mrf.SetChannel(channel);
    
    //Analog input
    AnalogIn button(p20);   //Analog input from the light sensor 
    
    //Variable to read values
    float val = 1;
    int begin = 0;
    int end = 0;
    int current = 0;
    
    //Start the timer
    timer.start();  

    while(true) { 
           
        //Try to receive some data
        rxLen = rf_receive(rxBuffer, 128);
        
        if(rxLen > 0) {
            
                //Switch on the Led and start the timer
                printf("Received input\n");
                led1 = 1;
                begin = timer.read_ms();
                end = begin + 2000;
                strcpy(txBuffer, "n");
                
                //Loop for 1 sec and check for whack
                while(current < end){
                        
                    current = timer.read_ms();    
                    val = button.read();
                    if(val <= 0.4){                       
                        strcpy(txBuffer, "y"); ///send "y" if press
                        break;
                    }
                    
                }//end of 1 sec while loop
        
        led1 = 0; //Switch of the Led
        rf_send(txBuffer, strlen(txBuffer) + 1); // send data
        pc.printf("Sent: %s\r\n", txBuffer);
        
        }//end of if loop
            
        
              
    }// end of while true
    
}//end of main