Ben Katz
/
Quadrature_Test
quadrature testing
main.cpp
- Committer:
- benkatz
- Date:
- 2015-12-07
- Revision:
- 1:6e92984aacba
- Parent:
- 0:f3974679f594
File content as of revision 1:6e92984aacba:
#include "mbed.h" #include "FastPWM.h" //FastPWM duty(PA_3); Ticker loop; unsigned int old_velocity = 0; unsigned int velocity; AnalogOut output(A2); void EncoderInitialise(void) { // configure GPIO PA0 & PA1 as inputs for Encoder RCC->AHB1ENR |= 0x00000001; // Enable clock for GPIOA GPIOA->MODER |= GPIO_MODER_MODER0_1 | GPIO_MODER_MODER1_1 ; //PA0 & PA1 as Alternate Function /*!< GPIO port mode register, Address offset: 0x00 */ GPIOA->OTYPER |= GPIO_OTYPER_OT_0 | GPIO_OTYPER_OT_1 ; //PA0 & PA1 as Inputs /*!< GPIO port output type register, Address offset: 0x04 */ GPIOA->OSPEEDR |= GPIO_OSPEEDER_OSPEEDR0 | GPIO_OSPEEDER_OSPEEDR1 ; // Low speed /*!< GPIO port output speed register, Address offset: 0x08 */ GPIOA->PUPDR |= GPIO_PUPDR_PUPDR0_1 | GPIO_PUPDR_PUPDR1_1 ; // Pull Down /*!< GPIO port pull-up/pull-down register, Address offset: 0x0C */ GPIOA->AFR[0] |= 0x00000011 ; // AF01 for PA0 & PA1 /*!< GPIO alternate function registers, Address offset: 0x20-0x24 */ GPIOA->AFR[1] |= 0x00000000 ; // /*!< GPIO alternate function registers, Address offset: 0x20-0x24 */ // configure TIM2 as Encoder input RCC->APB1ENR |= 0x00000001; // Enable clock for TIM2 TIM2->CR1 = 0x0001; // CEN(Counter ENable)='1' < TIM control register 1 TIM2->SMCR = 0x0003; // SMS='011' (Encoder mode 3) < TIM slave mode control register TIM2->CCMR1 = 0xF1F1; // CC1S='01' CC2S='01' < TIM capture/compare mode register 1 TIM2->CCMR2 = 0x0000; // < TIM capture/compare mode register 2 TIM2->CCER = 0x0011; // CC1P CC2P < TIM capture/compare enable register TIM2->PSC = 0x0000; // Prescaler = (0+1) < TIM prescaler TIM2->ARR = 0xffffffff; // reload at 0xfffffff < TIM auto-reload register TIM2->CNT = 0x0000; //reset the counter before we use it } // Z Pulse routine void ZeroEncoderCount() { TIM2->CNT=0 ; //reset count to zero } void setp(void){ output.write_u16((TIM2->CNT)<<4); } void print_serial(void){ velocity = (TIM2->CNT); printf("%i\n\r",velocity-old_velocity); old_velocity = velocity; } int main() { EncoderInitialise() ; unsigned int EncoderPosition ; loop.attach(&setp, .000001); while (true) { // Print Encoder Quadrature count to debug port every 0.5 seconds //EncoderPosition = TIM2->CNT ; // Get current position from Encoder //printf("Encoder Position %i\r\n", EncoderPosition); //wait(0.1); } }