Diff: PositionSensor/PositionSensor.cpp

Revision:

0:4e1c4df6aabd

Child:

1:b8bceb4daed5

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/PositionSensor/PositionSensor.cpp	Fri Feb 05 00:52:53 2016 +0000
@@ -0,0 +1,80 @@
+
+#include "mbed.h"
+#include "PositionSensor.h"
+#include <math.h>
+
+
+    
+PositionSensorEncoder::PositionSensorEncoder(int CPR, float offset) {
+    _CPR = CPR;
+    _offset = offset;
+    
+    // Enable clock for GPIOA
+    __GPIOA_CLK_ENABLE(); //equivalent from hal_rcc.h
+ 
+    GPIOA->MODER   |= GPIO_MODER_MODER6_1 | GPIO_MODER_MODER7_1 ;           //PA6 & PA7 as Alternate Function   /*!< GPIO port mode register,               Address offset: 0x00      */
+    GPIOA->OTYPER  |= GPIO_OTYPER_OT_6 | GPIO_OTYPER_OT_7 ;                 //PA6 & PA7 as Inputs               /*!< GPIO port output type register,        Address offset: 0x04      */
+    GPIOA->OSPEEDR |= GPIO_OSPEEDER_OSPEEDR6 | GPIO_OSPEEDER_OSPEEDR7 ;     //Low speed                         /*!< GPIO port output speed register,       Address offset: 0x08      */
+    GPIOA->PUPDR   |= GPIO_PUPDR_PUPDR6_1 | GPIO_PUPDR_PUPDR7_1 ;           //Pull Down                         /*!< GPIO port pull-up/pull-down register,  Address offset: 0x0C      */
+    GPIOA->AFR[0]  |= 0x22000000 ;                                          //AF02 for PA6 & PA7                /*!< GPIO alternate function registers,     Address offset: 0x20-0x24 */
+    GPIOA->AFR[1]  |= 0x00000000 ;                                          //nibbles here refer to gpio8..15   /*!< GPIO alternate function registers,     Address offset: 0x20-0x24 */
+   
+    // configure TIM3 as Encoder input
+    // Enable clock for TIM3
+    __TIM3_CLK_ENABLE();
+ 
+    TIM3->CR1   = 0x0001;     // CEN(Counter ENable)='1'     < TIM control register 1
+    TIM3->SMCR  = TIM_ENCODERMODE_TI12;     // SMS='011' (Encoder mode 3)  < TIM slave mode control register
+    TIM3->CCMR1 = 0xf1f1;     // CC1S='01' CC2S='01'         < TIM capture/compare mode register 1
+    TIM3->CCMR2 = 0x0000;     //                             < TIM capture/compare mode register 2
+    TIM3->CCER  = 0x0011;     // CC1P CC2P                   < TIM capture/compare enable register
+    TIM3->PSC   = 0x0000;     // Prescaler = (0+1)           < TIM prescaler
+    TIM3->ARR   = 0xffffffff; // reload at 0xfffffff         < TIM auto-reload register
+  
+    TIM3->CNT = 0x8000;  //reset the counter before we use it  
+    
+    ZPulse = new InterruptIn(PB_0);
+    ZSense = new DigitalIn(PB_0);
+    ZPulse->enable_irq();
+    ZPulse->rise(this, &PositionSensorEncoder::ZeroEncoderCount);
+    ZPulse->mode(PullDown);
+    //TIM5->CCMR1 = 0xf1f1;     // CC1S='01' CC2S='01'         < TIM capture/compare mode register 1
+
+    
+    ZTest = new DigitalOut(PC_2);
+    ZTest->write(1);
+    //int state = 0;
+    
+    
+}
+ 
+float PositionSensorEncoder::GetMechPosition() {        //returns rotor angle in radians.
+    int raw = TIM3->CNT-0x8000;
+    if (raw < 0) raw += _CPR;
+    if (raw >= _CPR) raw -= _CPR;
+    return 6.28318530718f*(raw)/(float)_CPR + _offset;    
+}
+
+float PositionSensorEncoder::GetElecPosition() {        //returns rotor electrical angle in radians.
+    int raw = TIM3->CNT-0x8000;
+    if (raw < 0) raw += _CPR;
+    if (raw >= _CPR) raw -= _CPR;
+    float signed_elec = fmod((7.0f*(6.28318530718f*(raw)/(float)_CPR + _offset)), 6.28318530718f);
+    //float signed_elec = (7*(6.28318530718*(TIM3->CNT-0x8000)/(float)_CPR + _offset));
+    if (signed_elec < 0){
+        return signed_elec + 6.28318530718f;
+        }
+    else{
+        return signed_elec;
+        }
+}
+
+void PositionSensorEncoder::ZeroEncoderCount(void){
+    if (ZSense->read() == 1){
+        if (ZSense->read() == 1){
+            TIM3->CNT=0x8000;
+            state = !state;
+            ZTest->write(state);
+        }
+        }
+    }
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