touch.h

00001 /*
00002 Touchpad driver.
00003 
00004 CPV, 3/9/2009
00005 */
00006 
00007 #ifndef __TOUCHPAD_H__
00008 #define __TOUCHPAD_H__
00009 
00010 
00011 #include "mbed.h"
00012 #include "filters.h"
00013 
00014 
00015 class TouchpadChannel
00016 {
00017 public:
00018     void initialise(int min, int quantise_step);
00019     void tick(int v) { m_filter.tick(v); }
00020     int quantise(void);
00021     int operator()(void) { return m_quantised; }
00022     int get_raw(void) { return m_filter(); }
00023 
00024 protected:
00025     FilterBoxI m_filter;
00026     int m_min;
00027     int m_quantise_step;
00028     int m_quantised;
00029 };
00030 
00031 
00032 class Touchpad
00033 {
00034 public:
00035     Touchpad(PinName x0, PinName x1, PinName y0, PinName y1);
00036 
00037     void tick(void);
00038 
00039     int get_raw_x(void) { return m_ch_x.get_raw(); }
00040     int get_raw_y(void) { return m_ch_y.get_raw(); }
00041 
00042     int hotspot(void) { return (m_ch_x.quantise()>=0 && m_ch_y.quantise()>=0); }
00043     int get_hotspot_x(void) { return m_ch_x(); }
00044     int get_hotspot_y(void) { return m_ch_y(); }
00045 
00046 protected:
00047     TouchpadChannel m_ch_x;
00048     TouchpadChannel m_ch_y;
00049 
00050     PinName m_x0;
00051     PinName m_x1;
00052     PinName m_y0;
00053     PinName m_y1;
00054 
00055     int read(PinName drive_hi, PinName drive_lo, PinName read_hi, PinName read_lo);
00056     int read_x(void) { return read(m_x1,m_x0,m_y1,m_y0); }
00057     int read_y(void) { return read(m_y1,m_y0,m_x1,m_x0); }
00058 };
00059 
00060 
00061 #endif // __TOUCHPAD_H__