File content as of revision 0:0a76ae27065b:

/*
Touchpad driver.

CPV, 3/9/2009
*/

#include "touchpad.h"


void TouchpadChannel::initialise(int min, int quantise_step)
{
  m_min = min;
  m_quantise_step = quantise_step;
  m_filter.initialise(8);
  m_quantised = -1;
}


int TouchpadChannel::quantise(void)
{
  m_quantised = -1;
  int raw = m_filter();
  if (raw>m_min)
  {
    m_quantised = 0;
    while(raw>m_quantise_step)
    {
      raw -= m_quantise_step;
      m_quantised += 1;
    }
  }
  return m_quantised;
}


//===============================================


Touchpad::Touchpad(PinName x0, PinName x1, PinName y0, PinName y1)
{
  m_x0 = x0;
  m_x1 = x1;
  m_y0 = y0;
  m_y1 = y1;
  m_ch_x.initialise(0.1*0xffff,0.16*0xffff);
  m_ch_y.initialise(0.1*0xffff,0.22*0xffff);
}


int Touchpad::read(PinName drive_hi, PinName drive_lo, PinName read_hi, PinName read_lo)
{
  DigitalOut out1(drive_hi);
  DigitalOut out0(drive_lo);
  AnalogIn in1(read_hi);
  AnalogIn in0(read_lo);
  out0 = 0;
  out1 = 1;
  return in1.read_u16();
}


void Touchpad::tick(void)
{
  m_ch_x.tick(read_x());
  m_ch_y.tick(read_y());
}