SG90.c 2.5 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566
  1. #include "main.h"
  2. static void SG90_TIM3_Init(void);
  3. static void SG90_Angle(float angle);
  4. SG90ClassStruct SG90Class = {
  5. SG90_TIM3_Init,
  6. SG90_Angle
  7. };
  8. #if 1
  9. #define SG90_TIM TIM2
  10. #define SG90_TIM_CLK RCC_APB1Periph_TIM2
  11. #define SG90_GPIO_PORT GPIOA
  12. #define SG90_GPIO_CLK RCC_APB2Periph_GPIOA
  13. #define SG90_GPIO_PIN GPIO_Pin_0
  14. #else
  15. #define SG90_TIM TIM3
  16. #define SG90_TIM_CLK RCC_APB1Periph_TIM3
  17. #define SG90_GPIO_PORT GPIOA
  18. #define SG90_GPIO_CLK RCC_APB2Periph_GPIOA
  19. #define SG90_GPIO_PIN GPIO_Pin_6
  20. #endif
  21. // PWM初始化 10000-1,144-1
  22. static void SG90_TIM3_Init(void)
  23. {
  24. GPIO_InitTypeDef GPIO_InitStructure;
  25. TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
  26. TIM_OCInitTypeDef TIM_OCInitStructure;
  27. RCC_APB2PeriphClockCmd(SG90_GPIO_CLK, ENABLE); //使能GPIO外设时钟使能
  28. RCC_APB2PeriphClockCmd(RCC_APB2Periph_AFIO, ENABLE);
  29. RCC_APB1PeriphClockCmd(SG90_TIM_CLK, ENABLE); //时钟使能
  30. //设置该引脚为复用输出功能,输出PWM脉冲波形
  31. GPIO_InitStructure.GPIO_Pin = SG90_GPIO_PIN;
  32. GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP; //复用推挽输出
  33. GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  34. GPIO_Init(SG90_GPIO_PORT, &GPIO_InitStructure);
  35. //定时器初始化
  36. TIM_TimeBaseStructure.TIM_Period = 10000-1; //设置在下一个更新事件装入活动的自动重装载寄存器周期的值
  37. TIM_TimeBaseStructure.TIM_Prescaler = 144-1; //设置用来作为TIMx时钟频率除数的预分频值
  38. TIM_TimeBaseStructure.TIM_ClockDivision = TIM_CKD_DIV1; //设置时钟分割:TDTS = Tck_tim
  39. TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; //TIM向上计数模式
  40. TIM_TimeBaseStructure.TIM_RepetitionCounter = 0;
  41. TIM_TimeBaseInit(SG90_TIM, &TIM_TimeBaseStructure); //根据指定的参数初始化TIMx的时间基数单位
  42. TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2; //选择定时器模式:TIM脉冲宽度调制模式2
  43. TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable; //比较输出使能
  44. TIM_OCInitStructure.TIM_Pulse = 0; //设置待装入捕获比较寄存器的脉冲值
  45. TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low; //输出极性:TIM输出比较极性高
  46. TIM_OC1Init(SG90_TIM, &TIM_OCInitStructure); //根据TIM_OCInitStruct中指定的参数初始化外设TIMx
  47. TIM_OC1PreloadConfig(SG90_TIM, TIM_OCPreload_Enable); //CH1预装载使能
  48. TIM_ARRPreloadConfig(SG90_TIM, ENABLE); //使能TIMx在ARR上的预装载寄存器
  49. TIM_Cmd(SG90_TIM, ENABLE); //使能TIMx
  50. TIM_CtrlPWMOutputs(SG90_TIM,ENABLE); //MOE 主输出使能
  51. }
  52. static void SG90_Angle(float angle)
  53. {
  54. angle = (uint16_t)(50.0 * angle / 9.0 + 250.0);
  55. TIM_SetCompare1(SG90_TIM, angle);
  56. }