Diff: TSISensor.cpp

Revision:

1:4dd9262cac47

Child:

3:1a60ef257879

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TSISensor.cpp	Thu Oct 11 14:00:48 2012 +0000
@@ -0,0 +1,231 @@
+/* Freescale Semiconductor Inc.
+ * (c) Copyright 2004-2005 Freescale Semiconductor, Inc.
+ * (c) Copyright 2001-2004 Motorola, Inc. 
+ *
+ * mbed Microcontroller Library
+ * (c) Copyright 2009-2012 ARM Limited.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
+ * and associated documentation files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
+ * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include "mbed.h"
+#include "TSISensor.h"
+
+#define NO_TOUCH                 0
+#define SLIDER_LENGTH           40 //LENGTH in mm
+#define TOTAL_ELECTRODE          2
+
+#define TSI0a        0
+#define TSI1         1
+#define TSI2         2
+#define TSI3         3
+#define TSI4         4
+#define TSI5         5
+#define TSI6         6
+#define TSI7         7
+#define TSI8         8
+#define TSI9         9
+#define TSI10        10
+#define TSI11        11
+#define TSI12        12
+#define TSI13        13
+#define TSI14        14
+#define TSI15        15
+
+/*Chose the correct TSI channel for the electrode number*/
+#define ELECTRODE0   TSI9
+#define ELECTRODE1   TSI10
+#define ELECTRODE2   TSI0a
+#define ELECTRODE3   TSI1
+#define ELECTRODE4   TSI2
+#define ELECTRODE5   TSI3
+#define ELECTRODE6   TSI4
+#define ELECTRODE7   TSI5
+#define ELECTRODE8   TSI6
+#define ELECTRODE9   TSI7
+#define ELECTRODE10  TSI8
+#define ELECTRODE11  TSI11
+#define ELECTRODE12  TSI12
+#define ELECTRODE13  TSI13
+#define ELECTRODE14  TSI14
+#define ELECTRODE15  TSI15
+
+#define THRESHOLD0   100
+#define THRESHOLD1   100
+#define THRESHOLD2   100
+#define THRESHOLD3   100
+#define THRESHOLD4   100
+#define THRESHOLD5   100
+#define THRESHOLD6   100
+#define THRESHOLD7   100
+#define THRESHOLD8   100
+#define THRESHOLD9   100
+#define THRESHOLD10   100
+#define THRESHOLD11   100
+#define THRESHOLD12   100
+#define THRESHOLD13   100
+#define THRESHOLD14   100
+#define THRESHOLD15   100
+
+static uint8_t total_electrode = TOTAL_ELECTRODE;
+static uint8_t elec_array[16]={ELECTRODE0,ELECTRODE1,ELECTRODE2,ELECTRODE3,ELECTRODE4,ELECTRODE5,
+                               ELECTRODE6,ELECTRODE7,ELECTRODE8,ELECTRODE9,ELECTRODE10,ELECTRODE11,
+                               ELECTRODE12,ELECTRODE13,ELECTRODE14,ELECTRODE15};
+static uint16_t gu16TSICount[16];
+static uint16_t gu16Baseline[16];
+static uint16_t gu16Threshold[16]={THRESHOLD0,THRESHOLD1,THRESHOLD2,THRESHOLD3,THRESHOLD4,THRESHOLD5,
+                                   THRESHOLD6,THRESHOLD7,THRESHOLD8,THRESHOLD9,THRESHOLD10,THRESHOLD11,
+                                   THRESHOLD12,THRESHOLD13,THRESHOLD14,THRESHOLD15};
+static uint16_t gu16Delta[16];
+static uint8_t ongoing_elec;
+static uint8_t end_flag = 1;
+
+static uint8_t SliderPercentegePosition[2] = {NO_TOUCH,NO_TOUCH};
+static uint8_t SliderDistancePosition[2] = {NO_TOUCH,NO_TOUCH};
+static uint32_t AbsolutePercentegePosition = NO_TOUCH;
+static uint32_t AbsoluteDistancePosition = NO_TOUCH;
+
+static void tsi_irq();
+
+TSISensor::TSISensor() {
+    SIM->SCGC5 |= SIM_SCGC5_PORTB_MASK;
+    SIM->SCGC5 |= SIM_SCGC5_TSI_MASK;
+
+    TSI0->GENCS |= (TSI_GENCS_ESOR_MASK
+                   | TSI_GENCS_MODE(0)
+                   | TSI_GENCS_REFCHRG(4)
+                   | TSI_GENCS_DVOLT(0)
+                   | TSI_GENCS_EXTCHRG(7)
+                   | TSI_GENCS_PS(4)
+                   | TSI_GENCS_NSCN(11)
+                   | TSI_GENCS_TSIIEN_MASK
+                   | TSI_GENCS_STPE_MASK
+                   );
+
+    TSI0->GENCS |= TSI_GENCS_TSIEN_MASK;
+
+    NVIC_SetVector(TSI0_IRQn, (uint32_t)&tsi_irq);
+    NVIC_EnableIRQ(TSI0_IRQn);
+
+    selfCalibration();
+}
+
+
+void TSISensor::selfCalibration(void)
+{
+    unsigned char cnt;
+    unsigned char trigger_backup;
+
+    TSI0->GENCS |= TSI_GENCS_EOSF_MASK;      // Clear End of Scan Flag
+    TSI0->GENCS &= ~TSI_GENCS_TSIEN_MASK;    // Disable TSI module
+
+    if(TSI0->GENCS & TSI_GENCS_STM_MASK)     // Back-up TSI Trigger mode from Application
+        trigger_backup = 1;
+    else
+        trigger_backup = 0;
+
+    TSI0->GENCS &= ~TSI_GENCS_STM_MASK;      // Use SW trigger
+    TSI0->GENCS &= ~TSI_GENCS_TSIIEN_MASK;    // Enable TSI interrupts
+
+    TSI0->GENCS |= TSI_GENCS_TSIEN_MASK;     // Enable TSI module
+
+    for(cnt=0; cnt < total_electrode; cnt++)  // Get Counts when Electrode not pressed
+    {
+        TSI0->DATA = ((elec_array[cnt] << TSI_DATA_TSICH_SHIFT) );
+        TSI0->DATA |= TSI_DATA_SWTS_MASK;
+        while(!(TSI0->GENCS & TSI_GENCS_EOSF_MASK));
+        TSI0->GENCS |= TSI_GENCS_EOSF_MASK;
+        gu16Baseline[cnt] = (TSI0->DATA & TSI_DATA_TSICNT_MASK);
+    }
+
+    TSI0->GENCS &= ~TSI_GENCS_TSIEN_MASK;    // Disable TSI module
+    TSI0->GENCS |= TSI_GENCS_TSIIEN_MASK;     // Enale TSI interrupt
+    if(trigger_backup)                      // Restore trigger mode
+        TSI0->GENCS |= TSI_GENCS_STM_MASK;
+    else
+        TSI0->GENCS &= ~TSI_GENCS_STM_MASK;
+
+    TSI0->GENCS |= TSI_GENCS_TSIEN_MASK;     // Enable TSI module
+
+    TSI0->DATA = ((elec_array[0]<<TSI_DATA_TSICH_SHIFT) );
+    TSI0->DATA |= TSI_DATA_SWTS_MASK;
+}
+
+
+void TSISensor::sliderRead(void ) {
+    if(end_flag) {
+        end_flag = 0;
+        if((gu16Delta[0] > gu16Threshold[0])||(gu16Delta[1] > gu16Threshold[1])) {
+            SliderPercentegePosition[0] = (gu16Delta[0]*100)/(gu16Delta[0]+gu16Delta[1]);
+            SliderPercentegePosition[1] = (gu16Delta[1]*100)/(gu16Delta[0]+gu16Delta[1]);
+            SliderDistancePosition[0] = (SliderPercentegePosition[0]* SLIDER_LENGTH)/100;
+            SliderDistancePosition[1] = (SliderPercentegePosition[1]* SLIDER_LENGTH)/100;
+            AbsolutePercentegePosition = ((100 - SliderPercentegePosition[0]) + SliderPercentegePosition[1])/2;
+            AbsoluteDistancePosition = ((SLIDER_LENGTH - SliderDistancePosition[0]) + SliderDistancePosition[1])/2;
+         } else {
+            SliderPercentegePosition[0] = NO_TOUCH;
+            SliderPercentegePosition[1] = NO_TOUCH;
+            SliderDistancePosition[0] = NO_TOUCH;
+            SliderDistancePosition[1] = NO_TOUCH;
+            AbsolutePercentegePosition = NO_TOUCH;
+            AbsoluteDistancePosition = NO_TOUCH;
+         }
+    }
+}
+
+float TSISensor::readPercentage() {
+    sliderRead();
+    return (float)AbsolutePercentegePosition/100.0;
+}
+
+uint8_t TSISensor::readDistance() {
+    sliderRead();
+    return AbsoluteDistancePosition;
+}
+
+
+static void changeElectrode(void)
+{
+    int16_t u16temp_delta;
+
+    gu16TSICount[ongoing_elec] = (TSI0->DATA & TSI_DATA_TSICNT_MASK);          // Save Counts for current electrode
+    u16temp_delta = gu16TSICount[ongoing_elec] - gu16Baseline[ongoing_elec];  // Obtains Counts Delta from callibration reference
+    if(u16temp_delta < 0)
+        gu16Delta[ongoing_elec] = 0;
+    else
+        gu16Delta[ongoing_elec] = u16temp_delta;
+
+    //Change Electrode to Scan
+    if(total_electrode > 1)  
+    {
+        if((total_electrode-1) > ongoing_elec)
+            ongoing_elec++;
+        else
+            ongoing_elec = 0;
+
+        TSI0->DATA = ((elec_array[ongoing_elec]<<TSI_DATA_TSICH_SHIFT) );
+        TSI0->DATA |= TSI_DATA_SWTS_MASK;
+    }
+}
+
+
+void tsi_irq(void)
+{
+    end_flag = 1;
+    TSI0->GENCS |= TSI_GENCS_EOSF_MASK; // Clear End of Scan Flag
+    changeElectrode();
+}
+