void touch_setup()
{

    //CTMUCON - CTMU Control register
    CTMUCON = 0x1090; //make sure CTMU is disabled
    // CTMU continues to run when emulator is stopped,CTMU continues
    // to run in Idle mode, Time Generation mode enabled, Edges are
    // blocked. No edge sequence order, Analog current source not
    // grounded, trigger output disabled, Edge2 polarity = positive level,
    // Edge2 source = source 0, Edge1 polarity = positive level,
    // Edge1 source = source 0, Set Edge status bits to zero

    //CTMUICON - CTMU Current Control Register
    CTMUICON = 0x0300;

    //setup ADC
    AD1PCFG = 0xFFDF;                       //RA3(AN5) is analog
    AD1CHS = 0x0005;                        //Positive input for MUX A is AN5
    AD1CON1 = 0x8000;                       

    AD1CON2 = 0x0000;                       //Vss & Vdd are references
                                            //MUX A, do not scan inputs, 16-word buffer
    AD1CON3 = 0x0000;
    AD1CSSL = 0;

    //enable CTMU
    CTMUCONbits.CTMUEN = 1;
}

unsigned int read_touch_button()
{
    unsigned int i;                         //needed from DELAY macro

    AD1CON1bits.SAMP = 1;                   //manual sampling start
    CTMUCONbits.IDISSEN = 1;                //drain charge on the circuit
    DELAY;                                  //wait 125uS
    CTMUCONbits.IDISSEN = 0;                //end draining

    CTMUCONbits.EDG1STAT = 1;               //begin charging circuit
    DELAY;
    CTMUCONbits.EDG1STAT = 0;               //stop charging circuit

    IFS0bits.AD1IF = 0;                     //make sure ADC int is not set
    AD1CON1bits.SAMP = 0;                   //and start conv.
    while(!IFS0bits.AD1IF);                 //wait for ADC to complete
    AD1CON1bits.DONE = 0;
    IFS0bits.AD1IF = 0;

    return ADC1BUF0;
}