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PositionSensor/PositionSensor.cpp
- Committer:
- benkatz
- Date:
- 2016-05-12
- Revision:
- 10:370851e6e132
- Parent:
- 9:d7eb815cb057
- Child:
- 11:c83b18d41e54
File content as of revision 10:370851e6e132:
#include "mbed.h"
#include "PositionSensor.h"
//#include <math.h>
PositionSensorSPI::PositionSensorSPI(int CPR, float offset, int ppairs){
//_CPR = CPR;
_CPR = CPR;
_ppairs = ppairs;
_offset = offset;
rotations = 0;
spi = new SPI(PC_12, PC_11, PC_10);
spi->format(16, 0);
cs = new DigitalOut(PA_15);
cs->write(1);
MechOffset = 0;
}
float PositionSensorSPI::GetMechPosition(){
cs->write(0);
int response = spi->write(0)>>4;
cs->write(1);
if(response - old_counts > _CPR/4){
rotations -= 1;
}
else if (response - old_counts < -_CPR/4){
rotations += 1;
}
old_counts = response;
MechPosition = (6.28318530718f * ((float) response+(_CPR*rotations)))/ (float)_CPR;
return MechPosition - MechOffset;
}
float PositionSensorSPI::GetElecPosition(){
cs->write(0);
int response = spi->write(0)>>4;
cs->write(1);
float elec = ((6.28318530718f/(float)_CPR) * (float) ((_ppairs*response)%_CPR)) - _offset;
if(elec < 0) elec += 6.28318530718f;
return elec;
}
float PositionSensorSPI::GetMechVelocity(){
return 0;
}
void PositionSensorSPI::ZeroPosition(){
rotations = 0;
MechOffset = GetMechPosition();
}
PositionSensorEncoder::PositionSensorEncoder(int CPR, float offset, int ppairs) {
_ppairs = ppairs;
_CPR = CPR;
_offset = offset;
MechPosition = 0;
// 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, maximum digital filtering
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 = CPR-1; // reload at 0xfffffff < TIM auto-reload register
TIM3->CNT = 0x000; //reset the counter before we use it
// Extra Timer for velocity measurement
__TIM2_CLK_ENABLE();
TIM3->CR2 = 0x030; //MMS = 101
TIM2->PSC = 0x03;
//TIM2->CR2 |= TIM_CR2_TI1S;
TIM2->SMCR = 0x24; //TS = 010 for ITR2, SMS = 100 (reset counter at edge)
TIM2->CCMR1 = 0x3;// CC1S = 11, IC1 mapped on TRC
//TIM2->CR2 |= TIM_CR2_TI1S;
TIM2->CCER |= TIM_CCER_CC1P;
//TIM2->CCER |= TIM_CCER_CC1NP;
TIM2->CCER |= TIM_CCER_CC1E;
TIM2->CR1 = 0x01; //CEN
TIM3->CR1 = 0x01; // CEN
ZPulse = new InterruptIn(PC_4);
ZSense = new DigitalIn(PC_4);
//ZPulse = new InterruptIn(PB_0);
//ZSense = new DigitalIn(PB_0);
ZPulse->enable_irq();
ZPulse->rise(this, &PositionSensorEncoder::ZeroEncoderCount);
//ZPulse->fall(this, &PositionSensorEncoder::ZeroEncoderCountDown);
ZPulse->mode(PullDown);
flag = 0;
//ZTest = new DigitalOut(PC_2);
//ZTest->write(1);
}
float PositionSensorEncoder::GetMechPosition() { //returns rotor angle in radians.
int raw = TIM3->CNT;
float unsigned_mech = (6.28318530718f/(float)_CPR) * (float) ((raw)%_CPR);
return (float) unsigned_mech;// + 6.28318530718f* (float) rotations;
}
float PositionSensorEncoder::GetElecPosition() { //returns rotor electrical angle in radians.
int raw = TIM3->CNT;
float elec = ((6.28318530718f/(float)_CPR) * (float) ((_ppairs*raw)%_CPR)) - _offset;
if(elec < 0) elec += 6.28318530718f;
return elec;
}
float PositionSensorEncoder::GetElecVelocity(){
float rawPeriod = TIM2->CCR1; //Clock Ticks
float dir = (((TIM3->CR1)>>4)&1)*2-1; // +/- 1
return dir*_ppairs*90000000.0f*(6.28318530718f/(float)_CPR)/rawPeriod;
}
float PositionSensorEncoder::GetMechVelocity(){
float out = 0;
float rawPeriod = TIM2->CCR1; //Clock Ticks
float dir = -2.0f*(float)(((TIM3->CR1)>>4)&1)+1.0f; // +/- 1
float meas = dir*90000000.0f*(6.28318530718f/(float)_CPR)/rawPeriod;
if(meas == vel_old){
out = .95f*out_old;
}
else{
out = meas;
}
/*
if(abs(vel) < 2.0f){
vel = 0;
}
*/
vel_old = meas;
//out = .5f*out + .5f*out_old;
out_old = out;
return out;
}
void PositionSensorEncoder::ZeroEncoderCount(void){
if (ZSense->read() == 1 & flag == 0){
if (ZSense->read() == 1){
GPIOC->ODR ^= (1 << 4);
TIM3->CNT = 0x000;
//state = !state;
//ZTest->write(state);
GPIOC->ODR ^= (1 << 4);
//flag = 1;
}
}
}
void PositionSensorEncoder::ZeroEncoderCountDown(void){
if (ZSense->read() == 0){
if (ZSense->read() == 0){
GPIOC->ODR ^= (1 << 4);
flag = 0;
float dir = -2.0f*(float)(((TIM3->CR1)>>4)&1)+1.0f;
if(dir != dir){
dir = dir;
rotations += dir;
}
GPIOC->ODR ^= (1 << 4);
}
}
}