counter.cpp

00001 
00002 #include "mbed.h"
00003 #include "stm32f4xx.h"
00004 #include "stm32f4xx_hal_tim_ex.h"
00005 
00006 TIM_HandleTypeDef timer;
00007 TIM_Encoder_InitTypeDef encoder;
00008 
00009 //direction to PA_9 -- step to PA_8
00010 
00011 int main(){
00012      GPIO_InitTypeDef GPIO_InitStruct;
00013         __TIM1_CLK_ENABLE();
00014         __GPIOA_CLK_ENABLE();
00015         GPIO_InitStruct.Pin = GPIO_PIN_8 | GPIO_PIN_9;
00016         GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
00017         GPIO_InitStruct.Pull = GPIO_PULLDOWN;
00018         GPIO_InitStruct.Speed = GPIO_SPEED_HIGH;
00019         GPIO_InitStruct.Alternate = GPIO_AF1_TIM1;
00020         HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
00021         
00022     timer.Instance = TIM1;
00023     timer.Init.Period = 0xffff;
00024     timer.Init.Prescaler = 1;
00025     timer.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
00026     timer.Init.CounterMode = TIM_COUNTERMODE_UP;
00027      
00028     encoder.EncoderMode = TIM_ENCODERMODE_TI1; 
00029     encoder.IC1Filter = 0x0f;
00030     encoder.IC1Polarity = TIM_INPUTCHANNELPOLARITY_RISING; //step signal
00031     encoder.IC1Prescaler = TIM_ICPSC_DIV1;
00032     encoder.IC1Selection = TIM_ICSELECTION_DIRECTTI;
00033 
00034     encoder.IC2Filter = 0x0f;
00035     encoder.IC2Polarity = TIM_INPUTCHANNELPOLARITY_BOTHEDGE;  //check direction  
00036     encoder.IC2Prescaler = TIM_ICPSC_DIV1;
00037     encoder.IC2Selection = TIM_ICSELECTION_INDIRECTTI;
00038  
00039     HAL_TIM_Encoder_Init(&timer, &encoder);
00040     HAL_TIM_Encoder_Start(&timer,TIM_CHANNEL_1);   
00041 
00042     
00043     TIM1->EGR = 1;           // Generate an update event
00044     TIM1->CR1 = 1;           // Enable the counter
00045 
00046 
00047  while (1) {
00048         int16_t count1;
00049         count1=TIM1->CNT; 
00050 
00051         printf("%d\r\n", count1);
00052         wait(1.0);
00053 
00054  };
00055 }