使用Timer4的CH1输出占空比50%,频率800KHz的PWM波形
4 void TimerConfig(void) 5 { 6 timer_deinit(TIMER4); 7 rcu_periph_clock_enable(RCU_GPIOA); 8 rcu_periph_clock_enable(RCU_GPIOC); 9 rcu_periph_clock_enable(RCU_TIMER4); 10 11 timer_internal_clock_config(TIMER4); //选择内部时钟CK_TIMER(200M) 12
16 17 gpio_mode_set(GPIOA, GPIO_MODE_AF, GPIO_PUPD_NONE, GPIO_PIN_1);//这里要注意,配置成GPIO_MODE_OUTPUT就无法输出PWM波形了!!!
18 gpio_output_options_set(GPIOA, GPIO_OTYPE_PP, GPIO_OSPEED_50MHZ, GPIO_PIN_1);
19 gpio_af_set(GPIOA, GPIO_AF_2, GPIO_PIN_1);
21 /* TIMER1配置为0.1ms定时 */
22 timer_parameter_struct timer_initpara;
23
24 timer_initpara.prescaler = 4;
25 timer_initpara.clockdivision = TIMER_CKDIV_DIV1;//根据prescaler,clockdivision最终该定时器时钟评率为1M
26 timer_initpara.alignedmode = TIMER_COUNTER_EDGE;//触发方式设置根据边沿决定
27 timer_initpara.counterdirection = TIMER_COUNTER_UP;//设置为上升沿触发
28 timer_initpara.period = 49;//设置为0.1ms触发一次
29 timer_initpara.repetitioncounter = 0;
30 timer_init(TIMER4, &timer_initpara);
31
32 /* TIMER的CH1配置为PWM输出:边触发,这样保证每0.1ms产生一次触发 */
33 timer_oc_parameter_struct timer_ocintpara;
35 timer_ocintpara.ocpolarity = TIMER_OC_POLARITY_HIGH;
36 timer_ocintpara.outputstate = TIMER_CCX_ENABLE;
37 timer_ocintpara.ocnpolarity = TIMER_OCN_POLARITY_HIGH;
38 timer_ocintpara.outputnstate = TIMER_CCXN_DISABLE;
39 timer_ocintpara.ocidlestate = TIMER_OC_IDLE_STATE_LOW;
40 timer_ocintpara.ocnidlestate = TIMER_OCN_IDLE_STATE_LOW;
41 timer_channel_output_config(TIMER4,TIMER_CH_1,&timer_ocintpara);
42
43 timer_channel_output_pulse_value_config(TIMER4, TIMER_CH_1, 25);
44 timer_channel_output_mode_config(TIMER4, TIMER_CH_1, TIMER_OC_MODE_PWM0);
45 timer_channel_output_shadow_config(TIMER4, TIMER_CH_1, TIMER_OC_SHADOW_DISABLE);
46
47 /* 使能TIMERx_CAR寄存器的影子寄存器 */
48 timer_auto_reload_shadow_enable(TIMER4);
51
52 timer_enable(TIMER4);
55
56 return;
57 }
测量PA1,即可看到800KHz的PWM波形
下面这个是根据官方配置应用的,跟上面的差不多一样。
1 /*!************************************************************************************************** 2 \brief 用于LCD_PWM (200-1KHz) 3 ****************************************************************************************************/ 4 void Timer3_init(void) 5 { 6 timer_deinit(TIMER3); 7 8 timer_parameter_struct timer_initpara; 9 timer_oc_parameter_struct timer_ocintpara; 10 11 timer_initpara.prescaler = (1999);//200/2000/500 = 200hz 12 timer_initpara.clockdivision = TIMER_CKDIV_DIV1;//根据prescaler,clockdivision最终该定时器时钟频率为1M 13 timer_initpara.alignedmode = TIMER_COUNTER_EDGE;//触发方式设置根据边沿决定 14 timer_initpara.counterdirection = TIMER_COUNTER_UP;//设置为上升沿触发 15 timer_initpara.period = 499;//99-499->1000Hz~200Hz 16 timer_initpara.repetitioncounter = 0; 17 timer_init(TIMER3, &timer_initpara); 18 19 /* CH1 configuration in PWM mode0 */ 20 timer_ocintpara.ocpolarity = TIMER_OC_POLARITY_HIGH; 21 timer_ocintpara.outputstate = TIMER_CCX_ENABLE; 22 timer_ocintpara.ocnpolarity = TIMER_OCN_POLARITY_HIGH; 23 timer_ocintpara.outputnstate = TIMER_CCXN_DISABLE; 24 timer_ocintpara.ocidlestate = TIMER_OC_IDLE_STATE_LOW; 25 timer_ocintpara.ocnidlestate =TIMER_OCN_IDLE_STATE_LOW; 26 timer_channel_output_config(TIMER3, TIMER_CH_1, &timer_ocintpara); 27 28 timer_channel_output_pulse_value_config(TIMER3, TIMER_CH_1, 25);//设置通道占空比 29 timer_channel_output_mode_config(TIMER3, TIMER_CH_1, TIMER_OC_MODE_PWM0); 30 timer_channel_output_shadow_config(TIMER3, TIMER_CH_1, TIMER_OC_SHADOW_DISABLE); 31 32 timer_auto_reload_shadow_enable(TIMER3); 33 34 timer_enable(TIMER3); 35 }