【AT-START-F425测评】 五、定时器中断代码简析及呼吸灯实现

kit7828

【AT-START-F425测评】 五、定时器中断代码简析及呼吸灯实现 [复制链接]

 

雅特力AT32提供了较完整的Demo例程，其中tmr例程还是非常丰富的，其中有个7_pwm_output的例程，7个管脚分别输出PWM。Readme文件中有英文说明

  - tmr1_ch1  --->  pa8
  - tmr1_ch1c --->  pb13
  - tmr1_ch2  --->  pa9
  - tmr1_ch2c --->  pb14
  - tmr1_ch3  --->  pa10
  - tmr1_ch3c --->  pb15
  - tmr1_ch4  --->  pa11

查询手册，可以看到定时器各管脚的复用情况

       可以看到，复用使用MUX2。

具体的代码部分为

int main(void)
{
	uint8_t  dir = 0;
  system_clock_config();

  at32_board_init();

  /* get system clock */
  crm_clocks_freq_get(&crm_clocks_freq_struct);

  /* turn led2/led3/led4 on */
  at32_led_on(LED2);
  at32_led_on(LED3);
  at32_led_on(LED4);

  /* enable tmr1/gpioa/gpiob clock */
  crm_periph_clock_enable(CRM_TMR1_PERIPH_CLOCK, TRUE);
  crm_periph_clock_enable(CRM_GPIOA_PERIPH_CLOCK, TRUE);
//  crm_periph_clock_enable(CRM_GPIOB_PERIPH_CLOCK, TRUE);

  /* timer1 output pin Configuration */
  gpio_init_struct.gpio_pins = GPIO_PINS_8 | GPIO_PINS_9 | GPIO_PINS_10 |GPIO_PINS_11;
  gpio_init_struct.gpio_mode = GPIO_MODE_MUX;
  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
  gpio_init(GPIOA, &gpio_init_struct);

//  gpio_init_struct.gpio_pins = GPIO_PINS_13 | GPIO_PINS_14 | GPIO_PINS_15;
//  gpio_init_struct.gpio_mode = GPIO_MODE_MUX;
//  gpio_init_struct.gpio_out_type = GPIO_OUTPUT_PUSH_PULL;
//  gpio_init_struct.gpio_pull = GPIO_PULL_NONE;
//  gpio_init_struct.gpio_drive_strength = GPIO_DRIVE_STRENGTH_STRONGER;
//  gpio_init(GPIOB, &gpio_init_struct);

  gpio_pin_mux_config(GPIOA, GPIO_PINS_SOURCE8, GPIO_MUX_2);
  gpio_pin_mux_config(GPIOA, GPIO_PINS_SOURCE9, GPIO_MUX_2);
  gpio_pin_mux_config(GPIOA, GPIO_PINS_SOURCE10, GPIO_MUX_2);
  gpio_pin_mux_config(GPIOA, GPIO_PINS_SOURCE11, GPIO_MUX_2);
//  gpio_pin_mux_config(GPIOB, GPIO_PINS_SOURCE13, GPIO_MUX_2);
//  gpio_pin_mux_config(GPIOB, GPIO_PINS_SOURCE14, GPIO_MUX_2);
//  gpio_pin_mux_config(GPIOB, GPIO_PINS_SOURCE15, GPIO_MUX_2);


  /* tmr1 configuration generate 7 pwm signals with 4 different duty cycles:
   prescaler = 0, tmr1 counter clock = system_core_clock

   the objective is to generate 7 pwm signal at 17.57 khz:
     - tim1_period = (system_core_clock / 17570) - 1
   the channel 1 and channel 1c duty cycle is set to 50%
   the channel 2 and channel 2c duty cycle is set to 37.5%
   the channel 3 and channel 3c duty cycle is set to 25%
   the channel 4 duty cycle is set to 12.5%
   the timer pulse is calculated as follows:
     - channelxpulse = duty_cycle * (tim1_period - 1) / 100 */
  
	//类似stm32的ARR，自动重新装载寄存器
  /* compute the value to be set in arr regiter to generate signal frequency at 17.57 khz */
  //timer_period = (crm_clocks_freq_struct.sclk_freq / 17570 ) - 1;
  
	//一下分别根据周期计算占空比
  /* compute c1dt value to generate a duty cycle at 50% for channel 1 and 1c */
 // channel1_pulse = (uint16_t)(((uint32_t) 5 * (timer_period - 1)) / 10);
  
  /* compute c2dt value to generate a duty cycle at 37.5%  for channel 2 and 2c */
  //channel2_pulse = (uint16_t)(((uint32_t) 375 * (timer_period - 1)) / 1000);
  
  /* compute c3dt value to generate a duty cycle at 25%  for channel 3 and 3c */
  //channel3_pulse = (uint16_t)(((uint32_t) 2 * (timer_period - 1)) / 100);
  
  /* compute c4dt value to generate a duty cycle at 12.5%  for channel 4 */
  //channel4_pulse = (uint16_t)(((uint32_t) 125 * (timer_period- 1)) / 1000);

	//原代码直接用系统主频进行计数，不分频
	//tmr_base_init(TMR1, timer_period, 0);
	//更改为分频96，及定时器主频为  96Mhz / (95 +1) = 1Mhz
	//更改Arr 为 500， 实际计数为501个
  tmr_base_init(TMR1,  500,  95);
  tmr_cnt_dir_set(TMR1, TMR_COUNT_UP);		//向上计数方式
	tmr_clock_source_div_set(TMR1, TMR_CLOCK_DIV1);		//采用预分频的频率
	
  /* channel 1, 2, 3 and 4 configuration in output mode */
  tmr_output_default_para_init(&tmr_output_struct);
  tmr_output_struct.oc_mode = TMR_OUTPUT_CONTROL_PWM_MODE_B;
  tmr_output_struct.oc_output_state = TRUE;
  tmr_output_struct.oc_polarity = TMR_OUTPUT_ACTIVE_LOW;
  tmr_output_struct.oc_idle_state = TRUE;
  tmr_output_struct.occ_output_state = TRUE;
  tmr_output_struct.occ_polarity = TMR_OUTPUT_ACTIVE_HIGH;
  tmr_output_struct.occ_idle_state = FALSE;
  
  // channel 1  通道1配置，以及设置占空比
  tmr_output_channel_config(TMR1, TMR_SELECT_CHANNEL_1, &tmr_output_struct);
  tmr_channel_value_set(TMR1, TMR_SELECT_CHANNEL_1, channel1_pulse);
  
  // channel 2  通道2配置，以及设置占空比
  tmr_output_channel_config(TMR1, TMR_SELECT_CHANNEL_2, &tmr_output_struct);
  tmr_channel_value_set(TMR1, TMR_SELECT_CHANNEL_2, channel2_pulse);
  
  // channel 3  通道3配置，以及设置占空比
  tmr_output_channel_config(TMR1, TMR_SELECT_CHANNEL_3, &tmr_output_struct);
  tmr_channel_value_set(TMR1, TMR_SELECT_CHANNEL_3, channel3_pulse);
  
  // channel 4  通道4配置，以及设置占空比
  tmr_output_channel_config(TMR1, TMR_SELECT_CHANNEL_4, &tmr_output_struct);
  tmr_channel_value_set(TMR1, TMR_SELECT_CHANNEL_4, channel4_pulse);

  /* output enable */
  tmr_output_enable(TMR1, TRUE);
  
  /* enable tmr1 */
  tmr_counter_enable(TMR1, TRUE);

	channel3_pulse = 100;
	
  while(1)
  {
			//设置呼吸方式，最大值时递减，最小值时递增
			if(dir)channel3_pulse++; 
			else channel3_pulse--;  
			
			if(channel3_pulse>=500)dir=0; 
			if(channel3_pulse==0)dir=1; 
	
			//赋值占空比
			TMR1->c3dt = channel3_pulse;
			delay_ms(2);
			
  }
}

用的是高级定时器TMR1实现的。

 

评测的时候发现PA11没有占空比信号，通过万用表检测，发现排针（PA11）和MCU的管脚之间断开了，不知道是什么原因，个人在使用过程中对开发板的保护还是蛮好的，由此推断应该是出厂没有完全检测管脚，也给厂家提个醒。

soso

建议收到，期待后续：）

lugl4313820

旁边这个是神马神器呀，看着有点象ESP8266？

freebsder

板子不良？作为评估板这有点尴尬了。

kit7828

lugl4313820 发表于 2022-4-29 09:27 旁边这个是神马神器呀，看着有点象ESP8266？

网友火眼金睛啊，旁边是自己设计的stm32的开发板底板，确实用了8266。

littleshrimp

用镊子拨一下PA11引脚，看会不会变形，一搬LQFP封装没焊好用这种方法能试出来。