一，原理
输出方波原理：利用输出比较模式的电平翻转模式，cnt从零开始一直在记数，当到比较值得时候电平翻转。为了实现输出方波，我们可以每次翻转都让记数值加100，这样就能达到输出周期为200的方波了，这里的预分频系数给的是80，所以cnt的时钟是1MHZ，也就是说记一个数1us。
输出不同占空比的pwm波：和输出方波类似，都是cnt记数然后和比较寄存器里面的值相比较，不同的是这次选泽定时器的pwm模式。总结下来就是cnt中的值控制周期，比较寄存器arr控制占空比。
用什么定时器和通道可以参考下表
二，cubemax的相关配置
1，方波的配置（这里选择的是定时器4的通道一和通道二）
1）定时器的配置
2）引脚配置
3）中断的相关配置
2，不同占空比pwm波的相关配置（利用定时器15的通道一和通道二）
1）定时器配置
2）引脚配置
三，keil源码
1，输出两路方波
pwm.c
TIM_HandleTypeDef htim4;void HAL_TIM_MspPostInit(TIM_HandleTypeDef* timHandle)
{
GPIO_InitTypeDef GPIO_InitStruct = {0};
if(timHandle->Instance==TIM4)
{
/* USER CODE BEGIN TIM4_MspPostInit 0 */
/* USER CODE END TIM4_MspPostInit 0 */
__HAL_RCC_GPIOA_CLK_ENABLE();
/**TIM4 GPIO Configuration
PA11 ------> TIM4_CH1
PA12 ------> TIM4_CH2
*/
GPIO_InitStruct.Pin = GPIO_PIN_11|GPIO_PIN_12;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH;
GPIO_InitStruct.Alternate = GPIO_AF10_TIM4;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* USER CODE BEGIN TIM4_MspPostInit 1 */
/* USER CODE END TIM4_MspPostInit 1 */
}
}
void PWM_output_TIM4_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
htim4.Instance = TIM4;
htim4.Init.Prescaler = 79;
htim4.Init.CounterMode = TIM_COUNTERMODE_UP;
htim4.Init.Period = 65535;
htim4.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim4.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_ENABLE;
if (HAL_TIM_Base_Init(&htim4) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim4, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_TIM_OC_Init(&htim4) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim4, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_TOGGLE;
sConfigOC.Pulse = 100;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
if (HAL_TIM_OC_ConfigChannel(&htim4, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
Error_Handler();
}
sConfigOC.Pulse = 100;
if (HAL_TIM_OC_ConfigChannel(&htim4, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
{
Error_Handler();
}
HAL_TIM_MspPostInit(&htim4);
}pwm.h
extern TIM_HandleTypeDef htim4;
void PWM_output_TIM4_Init(void);main.h
初始化
PWM_output_TIM4_Init();
HAL_TIM_OC_Start_IT(&htim4,TIM_CHANNEL_1);
HAL_TIM_OC_Start_IT(&htim4,TIM_CHANNEL_2);中断回调函数
void HAL_TIM_OC_DelayElapsedCallback(TIM_HandleTypeDef *htim)
{
if(htim->Instance == TIM4)
{
if(htim->Channel == HAL_TIM_ACTIVE_CHANNEL_1)
{
__HAL_TIM_SET_COMPARE(htim,TIM_CHANNEL_1,(__HAL_TIM_GetCounter(htim)+100));
}
else if(htim->Channel == HAL_TIM_ACTIVE_CHANNEL_2)
{
__HAL_TIM_SET_COMPARE(htim,TIM_CHANNEL_2,(__HAL_TIM_GetCounter(htim)+600));
}
}
}
中断
void TIM4_IRQHandler(void)
{
/* USER CODE BEGIN TIM4_IRQn 0 */
/* USER CODE END TIM4_IRQn 0 */
HAL_TIM_IRQHandler(&htim4);
/* USER CODE BEGIN TIM4_IRQn 1 */
/* USER CODE END TIM4_IRQn 1 */
}GPIO的初始化
else if(tim_baseHandle->Instance==TIM4)
{
/* USER CODE BEGIN TIM4_MspInit 0 */
/* USER CODE END TIM4_MspInit 0 */
/* TIM4 clock enable */
__HAL_RCC_TIM4_CLK_ENABLE();
/* TIM4 interrupt Init */
HAL_NVIC_SetPriority(TIM4_IRQn, 3, 0);
HAL_NVIC_EnableIRQ(TIM4_IRQn);
/* USER CODE BEGIN TIM4_MspInit 1 */
/* USER CODE END TIM4_MspInit 1 */
}显示
sprintf((char*)Lcd_Disp_String,"PWM2_duty:%4.2f%%",PWM2_duty);
LCD_DisplayStringLine(Line8,Lcd_Disp_String);
sprintf((char*)Lcd_Disp_String,"PWM1_duty:%4.2f%%",PWM1_duty);
LCD_DisplayStringLine(Line9,Lcd_Disp_String); 2，输出两路不同占空比的pwm波
pwm.c
TIM_HandleTypeDef htim15;void PWM_output_TIM15_Init(void)
{
TIM_ClockConfigTypeDef sClockSourceConfig = {0};
TIM_MasterConfigTypeDef sMasterConfig = {0};
TIM_OC_InitTypeDef sConfigOC = {0};
TIM_BreakDeadTimeConfigTypeDef sBreakDeadTimeConfig = {0};
htim15.Instance = TIM15;
htim15.Init.Prescaler = 79;
htim15.Init.CounterMode = TIM_COUNTERMODE_UP;
htim15.Init.Period = 999;
htim15.Init.ClockDivision = TIM_CLOCKDIVISION_DIV1;
htim15.Init.RepetitionCounter = 79;
htim15.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
if (HAL_TIM_Base_Init(&htim15) != HAL_OK)
{
Error_Handler();
}
sClockSourceConfig.ClockSource = TIM_CLOCKSOURCE_INTERNAL;
if (HAL_TIM_ConfigClockSource(&htim15, &sClockSourceConfig) != HAL_OK)
{
Error_Handler();
}
if (HAL_TIM_PWM_Init(&htim15) != HAL_OK)
{
Error_Handler();
}
sMasterConfig.MasterOutputTrigger = TIM_TRGO_RESET;
sMasterConfig.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
if (HAL_TIMEx_MasterConfigSynchronization(&htim15, &sMasterConfig) != HAL_OK)
{
Error_Handler();
}
sConfigOC.OCMode = TIM_OCMODE_PWM1;
sConfigOC.Pulse = 300;
sConfigOC.OCPolarity = TIM_OCPOLARITY_HIGH;
sConfigOC.OCNPolarity = TIM_OCNPOLARITY_HIGH;
sConfigOC.OCFastMode = TIM_OCFAST_DISABLE;
sConfigOC.OCIdleState = TIM_OCIDLESTATE_RESET;
sConfigOC.OCNIdleState = TIM_OCNIDLESTATE_RESET;
if (HAL_TIM_PWM_ConfigChannel(&htim15, &sConfigOC, TIM_CHANNEL_1) != HAL_OK)
{
Error_Handler();
}
sConfigOC.Pulse = 600;
if (HAL_TIM_PWM_ConfigChannel(&htim15, &sConfigOC, TIM_CHANNEL_2) != HAL_OK)
{
Error_Handler();
}
sBreakDeadTimeConfig.OffStateRunMode = TIM_OSSR_DISABLE;
sBreakDeadTimeConfig.OffStateIDLEMode = TIM_OSSI_DISABLE;
sBreakDeadTimeConfig.LockLevel = TIM_LOCKLEVEL_OFF;
sBreakDeadTimeConfig.DeadTime = 0;
sBreakDeadTimeConfig.BreakState = TIM_BREAK_DISABLE;
sBreakDeadTimeConfig.BreakPolarity = TIM_BREAKPOLARITY_HIGH;
sBreakDeadTimeConfig.BreakFilter = 0;
sBreakDeadTimeConfig.AutomaticOutput = TIM_AUTOMATICOUTPUT_DISABLE;
if (HAL_TIMEx_ConfigBreakDeadTime(&htim15, &sBreakDeadTimeConfig) != HAL_OK)
{
Error_Handler();
}
HAL_TIM_MspPostInit(&htim15);
}
else if(timHandle->Instance==TIM15)
{
/* USER CODE BEGIN TIM15_MspPostInit 0 */
/* USER CODE END TIM15_MspPostInit 0 */
__HAL_RCC_GPIOA_CLK_ENABLE();
/**TIM15 GPIO Configuration
PA2 ------> TIM15_CH1
PA3 ------> TIM15_CH2
*/
GPIO_InitStruct.Pin = GPIO_PIN_2|GPIO_PIN_3;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
GPIO_InitStruct.Alternate = GPIO_AF9_TIM15;
HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);
/* USER CODE BEGIN TIM15_MspPostInit 1 */
/* USER CODE END TIM15_MspPostInit 1 */
}
pwm.h
extern TIM_HandleTypeDef htim15;
void PWM_output_TIM15_Init(void);main.h
PWM_output_TIM15_Init();
HAL_TIM_PWM_Start(&htim15,TIM_CHANNEL_1);
HAL_TIM_PWM_Start(&htim15,TIM_CHANNEL_2);