tsi_sensor.h

00001 /* Freescale Semiconductor Inc.
00002  *
00003  * mbed Microcontroller Library
00004  * (c) Copyright 2009-2012 ARM Limited.
00005  *
00006  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00007  * and associated documentation files (the "Software"), to deal in the Software without
00008  * restriction, including without limitation the rights to use, copy, modify, merge, publish,
00009  * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
00010  * Software is furnished to do so, subject to the following conditions:
00011  *
00012  * The above copyright notice and this permission notice shall be included in all copies or
00013  * substantial portions of the Software.
00014  *
00015  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00016  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00017  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00018  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00019  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00020  */
00021 
00022 /* This defines will be replaced by PinNames soon */
00023 #if defined (TARGET_KL25Z) || defined (TARGET_KL46Z)
00024   #define ELEC0 9
00025   #define ELEC1 10
00026 #elif defined (TARGET_KL05Z)
00027   #define ELEC0 9
00028   #define ELEC1 8
00029 #else
00030   #error TARGET NOT DEFINED
00031 #endif
00032 
00033 #ifndef TSISENSOR_H
00034 #define TSISENSOR_H
00035 
00036 
00037 /**
00038 * TSISensor example
00039 *
00040 * @code
00041 * #include "mbed.h"
00042 * #include "TSISensor.h"
00043 *
00044 * int main(void) {
00045 *    DigitalOut led(LED_GREEN);
00046 *    TSIElectrode elec0(9);
00047 *    TSIElectrode elec1(10);
00048 *    TSIAnalogSlider tsi(elec0, elec1, 40);
00049 *
00050 *    while (true) {
00051 *        printf("slider percentage: %f%\r\n", tsi.readPercentage());
00052 *        printf("slider distance: %dmm\r\n", tsi.readDistance());
00053 *        wait(1);
00054 *        led = !led;
00055 *    }
00056 * }
00057 * @endcode
00058 */
00059 #define NO_TOUCH 0
00060 
00061 /** TSI Electrode with simple data required for touch detection.
00062  */
00063 class TSIElectrode {
00064 public:
00065     /** Initialize electrode.
00066      */
00067     TSIElectrode(PinName pin) : _threshold(100) {
00068         _channel = getTSIChannel(pin);
00069     }
00070 
00071     /** Initialize electrode.
00072      */
00073     TSIElectrode(uint32_t tsi_channel) : _threshold(100) {
00074         _channel = (uint8_t)tsi_channel;
00075     }
00076     /** Set baseline.
00077      */
00078     void setBaseline(uint32_t baseline) {
00079         _baseline = (uint16_t)baseline;
00080     }
00081     /** Set threshold.
00082      */
00083     void setThreshold(uint32_t threshold) {
00084         _threshold = (uint16_t)threshold;
00085     }
00086     /** Set signal.
00087      */
00088     void setSignal(uint32_t signal) {
00089         _signal = (uint16_t)signal;
00090     }
00091     /** Get baseline.
00092      */
00093     uint32_t getBaseline() {
00094         return _baseline;
00095     }
00096     /** Get delta.
00097      */
00098     uint32_t getDelta() {
00099         int32_t delta = getSignal() - getBaseline();
00100         if (delta < 0) {
00101             return 0;
00102         } else {
00103             return delta;
00104         }
00105     }
00106     /** Get signal.
00107      */
00108     uint32_t getSignal() {
00109         return _signal;
00110     }
00111     /** Get threshold.
00112      */
00113     uint32_t getThreshold() {
00114         return _threshold;
00115     }
00116     /** Get channel.
00117      */
00118     uint32_t getChannel() {
00119         return _channel;
00120     }
00121     /** Get TSI Channel for PinName.
00122      *
00123      * @returns TSI channel ID for use in constructor of TSIAnalogSlider and TSIElectrode.
00124      * @throws compile-time error if target is not supported, or runtime error if pin does not match any channel.
00125      */
00126     static uint8_t getTSIChannel(PinName pin) {
00127 #if   defined(TARGET_KL25Z) || defined(TARGET_KL46Z) || defined (TARGET_KL05Z)       
00128         switch(pin) {
00129             //these are 
00130             case PTA0: return 1;
00131             case PTA1: return 2;
00132             case PTA2: return 3;
00133             case PTA3: return 4;
00134             case PTA4: return 5;
00135             case PTB0: return 0;
00136             case PTB1: return 6;
00137             case PTB2: return 7;
00138             case PTB3: return 8;
00139             case PTB16: return 9;
00140             case PTB17: return 10;
00141             case PTB18: return 11;
00142             case PTB19: return 12;
00143 #if   defined(TARGET_KL25Z) || defined(TARGET_KL46Z)
00144             case PTC0: return 13;
00145             case PTC1: return 14;
00146             case PTC2: return 15;
00147 #endif
00148             default: error("PinName provided to TSIElectrode::getTSIChannel() does not correspond to any known TSI channel.");
00149         }
00150 # else
00151     #error "Unknown target for TSIElectrode::getTSIChannel() - only supports KL25Z so far."
00152 # endif   
00153         return 0xFF; //should never get here
00154     }
00155     
00156 private:
00157     uint8_t  _channel;
00158     uint16_t _signal;
00159     uint16_t _baseline;
00160     uint16_t _threshold;
00161 };
00162 
00163 /** Analog slider which consists of two electrodes.
00164  */
00165 class TSIAnalogSlider {
00166 public:
00167     /**
00168      *
00169      *   Initialize the TSI Touch Sensor with the given PinNames
00170      */
00171     TSIAnalogSlider(PinName elec0, PinName elec1, uint32_t range);
00172     /**
00173      *   Initialize the TSI Touch Sensor
00174      */
00175     TSIAnalogSlider(uint32_t elec0, uint32_t elec1, uint32_t range);
00176     /**
00177      * Read Touch Sensor percentage value
00178      *
00179      * @returns percentage value between [0 ... 1]
00180      */
00181     float readPercentage();
00182     /**
00183      * Read Touch Sensor distance
00184      *
00185      * @returns distance in mm. The value is between [0 ... _range]
00186      */
00187     uint32_t readDistance();
00188     /** Get current electrode.
00189      */
00190     TSIElectrode* getCurrentElectrode() {
00191         return _current_elec;
00192     }
00193     /** Set current electrode which is being measured.
00194      */
00195     void setCurrentElectrode(TSIElectrode *elec){
00196         _current_elec = elec;
00197     }
00198     /** Get next electrode.
00199      */
00200     TSIElectrode* getNextElectrode(TSIElectrode* electrode) {
00201         if (electrode->getChannel() == _elec0.getChannel()) {
00202             return &_elec1;
00203         } else {
00204             return &_elec0;
00205         }
00206     }
00207     /** Return absolute distance position.
00208      */
00209     uint32_t getAbsoluteDistance() {
00210         return  _absolute_distance_pos;
00211     }
00212     /** Return absolute precentage position.
00213      */
00214     uint32_t getAbsolutePosition() {
00215         return _absolute_percentage_pos;
00216     }
00217     /** Set value to the scan in progress flag.
00218      */
00219     void setScan(uint32_t scan) {
00220         _scan_in_progress = scan;
00221     }
00222     /** Return instance to Analog slider. Used in tsi irq.
00223      */
00224     static TSIAnalogSlider *getInstance() {
00225         return _instance;
00226     }
00227 private:
00228     void initObject(void); //shared constructor code
00229     void sliderRead(void);
00230     void selfCalibration(void);
00231     void setSliderPercPosition(uint32_t elec_num, uint32_t position) {
00232         _percentage_position[elec_num] = position;
00233     }
00234     void setSliderDisPosition(uint32_t elec_num, uint32_t position) {
00235         _distance_position[elec_num] = position;
00236     }
00237     void setAbsolutePosition(uint32_t position) {
00238         _absolute_percentage_pos = position;
00239     }
00240     void setAbsoluteDistance(uint32_t distance) {
00241         _absolute_distance_pos = distance;
00242     }
00243 private:
00244     TSIElectrode  _elec0;
00245     TSIElectrode  _elec1;
00246     uint8_t       _scan_in_progress;
00247     TSIElectrode* _current_elec;
00248     uint8_t       _percentage_position[2];
00249     uint8_t       _distance_position[2];
00250     uint32_t      _absolute_percentage_pos;
00251     uint32_t      _absolute_distance_pos;
00252     uint8_t       _range;
00253 protected:
00254     static TSIAnalogSlider *_instance;
00255 };
00256 
00257 #endif