#include "decoder.h"
#include <stm32f4xx_tim.h>
#include <stm32f4xx_gpio.h>
#include <stm32f4xx_rcc.h>
//
//开发者只需要调用Decoder_Init()进行初始化
//然后调用Decoder_GetCnt或者Decoder_GetSpeed获得数据即可
uint16_t con_speed_period=20;//20ms采集一次数据,根据实际修改
float Decoder_GetSpeed(void)
{
static int16_t tmp;
static float re_dat=0;
tmp=(int16_t)Decoder_GetCnt();
if(tmp>20000)tmp=20000; //限幅
else if(tmp<-20000)tmp=-20000;
//编码器是1转输出256个正交脉冲，采用边缘计数，总共有256*4=1024
//进行单位换算
re_dat=(float)(((int16_t)tmp)*1000/(1024.0*con_speed_period));
return re_dat;
}
void Decoder_Init(void)
{
Decoder_GPIO_Init();
Decoder_TIM_Init();
}
void Decoder_GPIO_Init(void)
{
GPIO_InitTypeDef GPIO_InitStructure;
RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOE , ENABLE);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_11|GPIO_Pin_9;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF;
GPIO_InitStructure.GPIO_OType = GPIO_OType_OD;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
GPIO_InitStructure.GPIO_Speed = GPIO_Speed_100MHz;
GPIO_Init(GPIOE, &GPIO_InitStructure);
GPIO_PinAFConfig(GPIOE, GPIO_PinSource11, GPIO_AF_TIM1);
GPIO_PinAFConfig(GPIOE, GPIO_PinSource9, GPIO_AF_TIM1);
}
void Decoder_TIM_Init(void)
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_ICInitTypeDef TIM_ICInitStructure;
RCC_APB2PeriphClockCmd(RCC_APB2Periph_TIM1 , ENABLE);
TIM_DeInit(TIM1);
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period = ENCODER_TIM_PERIOD-1;
TIM_TimeBaseStructure.TIM_Prescaler = 0x00;
TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM1, &TIM_TimeBaseStructure);
TIM_EncoderInterfaceConfig(TIM1, TIM_EncoderMode_TI12, TIM_ICPolarity_Falling, TIM_ICPolarity_Falling);
TIM_ICStructInit(&TIM_ICInitStructure);
TIM_SetCounter(TIM1, 0);
TIM_Cmd(TIM1, ENABLE);
}
//返回计数值
int Decoder_GetCnt()
{
static int Decoder_cnt=0;
Decoder_cnt=(short)(TIM1 -> CNT);
TIM1 -> CNT=0;
return Decoder_cnt;
}
