窝的方法是用几片74数字电路产生一个多相交错的时钟,每个UC3843都同步到这些时钟上面,出来的PWM也是交错的了。这堆74可以用一小片CPLD代替,画出逻辑图烧进去就能用了。附件里是10相交错时钟的发生器,需要10倍PWM频率的时钟驱动哦
多相交错技术是低压大电流电源里面必备的技术之一,不光可以突破单个电感电流容量的限制,而且还能分散热点,更重要的是极大降低了有效值电流还提高了效率。多相交错电源里面每一路pwm都是需要相差一定角度的,比如三路交错就是需要三个相位之间相差120度的信号。本帖忽略匀流问题(实际中必须处理下否则相之间负载不平衡会让负载大的相烧掉)。如果启用了互补输出还可以做到三相交错的互补PWM。
STM32单片机是一种很常见性价比很高的32位单片机,最低端的STM32F0系列也有ADC,众多定时器等外设,于是本帖使用STM32F030K6为例,讲解高速多路交错PWM的产生方式,同样的原理也可以拓展到STM32F1/F3/F4系列和其他系列的单片机里面。在单片机里面有这么一种东西叫做时钟树,描述的是单片机内部每个模块的时钟频率,来源还有可用的分频/倍频选项,STM32F030K6的时钟树如图:
这个图是在STM32 CubeMX里面自动给出的,这个软件很不错,可以用图形界面来生成时钟树以及其他外设的初始化代码,再也不用死坑datasheet啦 哈哈哈(雾
STM32所有定时器的时钟都是接到APB1 Timer Clocks这里的,也就是说所有的定时器都是在同一时刻对Counter进行累加的。如果配置三个定时器为PWM输出模式,频率相同,但是开始计数的时间人为的叉开,就可以达到多相PWM的目的。我们可以配置三个定时器为同频率的PWM输出,然后再用一个定时器对这三个定时器在特定时间进行使能即可。GPIO的占用如下图:
TIM1, TIM16和TIM17分别输出三路100KHz的PWM以及他们的互补。 这是硬件初始化的代码,在main的主循环之前被调用,分别初始化了HAL库,系统时钟,还有用到的GPIO和定时器:
<code class="hljs cpp"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"> </span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title">hw_init</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params">(</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params">)</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"> </span></span></span></span></span></span></span></span></span></span></span></span></span></span>{ <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">/* Reset of all peripherals, Initializes the Flash interface and the Systick. */</span></span></span></span></span></span></span></span></span></span></span></span></span></span> HAL_Init(); SystemClock_Config(); GPIO_Init(); Timer1_Init(); Timer16_Init(); Timer17_Init(); Timer14_Init(); Timer_Sync_1_16_17(); }</code>
GPIO_Init();是把GPIO口变成PWM输出的,参见服见里面的platform.c这里就不贴出了。
TIM1, TIM16, TIM17的初始化代码很相似,这里就只贴TIM1的代码了:
<code class="hljs cpp"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword">static</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"> </span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"> </span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title"><span class="hljs-function"><span class="hljs-title">Timer1_Init</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params">(</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword"><span class="hljs-function"><span class="hljs-params"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params"><span class="hljs-function"><span class="hljs-params">)</span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"><span class="hljs-function"> </span></span></span></span></span></span></span></span></span></span></span></span></span>{ <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">__</span></span></span></span></span></span></span></span></span></span></span></span></span>HAL_RCC_TIM1_CLK_ENABLE();<span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">//启用TIM1外射的时钟,如果没开时钟根本不工作也不能被配置的哦</span></span></span></span></span></span></span></span></span></span></span></span></span> </code><code class="hljs php"> TIM1->CR1 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span></span></span>; TIM1->CR2 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span></span></span>; TIM1->DIER = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span></span></span>; TIM1->ARR = TIM_ARR_SW; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Auto-reload value : 100kHz overflow</span></span></span></span></span></span></span></span></span></span></span></span></span> TIM1->PSC = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span></span></span>; TIM1->CCR2 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span></span></span>; TIM1->CCMR1 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0x6800</span></span></span></span></span></span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// 110: PWM mode 1, up counting.</span></span></span></span></span></span></span></span></span></span></span></span></span> TIM1->CCER = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0x0050</span></span></span></span></span></span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// CH2 output enable with complement, active high</span></span></span></span></span></span></span></span></span></span></span></span></span> TIM1->BDTR = TIM_BDTR_DTG_Msk & TIM_DEADTIME; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Set dead-time</span></span></span></span></span></span></span></span></span></span></span></span></span> }</code>
这部分代码是很典型的把定时器配置成向上计数的PWM模式1并加互补死区的操作,就不详细解释了,如果有不懂可以参见RM0091(股沟得到)
重点来了!TIM14被用作了同步TIM1,TIM16和TIM17,但是这个同步并没有用到任何硬件上的同步(硬件也没有提供啊QAQ)
<code class="hljs php"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">static</span></span></span></span></span></span></span></span></span></span></span> void Timer14_Init(void) { __HAL_RCC_TIM14_CLK_ENABLE(); TIM14->CR1 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; TIM14->DIER = TIM_DIER_UIE; TIM14->ARR = TIM_ARR_PHSYNC; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Auto-reload value : 300kHz overflow</span></span></span></span></span></span></span></span></span></span></span> TIM14->PSC = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; NVIC_EnableIRQ(TIM14_IRQn); }</code>
首先还是开启时钟,这个千万别忘,很常见的错误,然后TIM14被配置成了自动重装模式,以300KHz的频率触发中断。300KHz的一个周期正好是我们想要的相位差的时间。Timer_Sync_1_16_17()首先确保TIM1,TIM14,TIM16和TIM17的计数器都是0,然后启动TIM14并等待TIM14被停止。
<code class="hljs objectivec"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">static</span></span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span> Timer_Sync_1_16_17(<span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">void</span></span></span></span></span></span></span></span></span></span></span>) { <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">extern</span></span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">volatile</span></span></span></span></span></span></span></span></span></span></span> uint32_t* tim_cr1; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Clear counter value</span></span></span></span></span></span></span></span></span></span></span> TIM14-><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in">CNT</span></span></span></span></span></span></span></span></span></span></span> = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; TIM1-><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in">CNT</span></span></span></span></span></span></span></span></span></span></span> = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; TIM16-><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in">CNT</span></span></span></span></span></span></span></span></span></span></span> = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; TIM17-><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in"><span class="hljs-built_in">CNT</span></span></span></span></span></span></span></span></span></span></span> = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Enable the synchronizer timer</span></span></span></span></span></span></span></span></span></span></span> TIM14->CR1 |= <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">1</span></span></span></span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Wait until the synchronization is done</span></span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">while</span></span></span></span></span></span></span></span></span></span></span> (tim_cr1 > <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span></span>);</code>
while那会让程序卡住,但是还是会进定时器中断的。TIM14中断的程序如下:
<code class="hljs php"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">static</span></span></span></span></span></span></span></span></span></span> uint32_t* tim_cr1 = &(TIM1->CR1); void TIM14_IRQHandler(void) { <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// This can be commented out, since update is the only source of interrupt</span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">if</span></span></span></span></span></span></span></span></span></span>(TIM14->SR & TIM_SR_UIF) { TIM14->SR &= ~TIM_SR_UIF; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// clear UIF flag</span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">if</span></span></span></span></span></span></span></span></span></span> (tim_cr1 > <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span>) { *tim_cr1 |= TIM_CR1_CEN; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Set the next timer to be enabled</span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">if</span></span></span></span></span></span></span></span></span></span> (tim_cr1 == &(TIM1->CR1)) { tim_cr1 = &(TIM16->CR1); } <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">else</span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">if</span></span></span></span></span></span></span></span></span></span> (tim_cr1 == &(TIM16->CR1)) { tim_cr1 = &(TIM17->CR1); } <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">else</span></span></span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">if</span></span></span></span></span></span></span></span></span></span> (tim_cr1 == &(TIM17->CR1)) { <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// All timers have been synchronized to the correct phase order</span></span></span></span></span></span></span></span></span></span> tim_cr1 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// No more CR1 to be set</span></span></span></span></span></span></span></span></span></span> <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Disable the timer</span></span></span></span></span></span></span></span></span></span> TIM14->CR1 &=~ TIM_CR1_CEN; } } <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">else</span></span></span></span></span></span></span></span></span></span> { <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Execute control routine here</span></span></span></span></span></span></span></span></span></span> } } <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// if(TIM14->SR & TIM_SR_UIF)</span></span></span></span></span></span></span></span></span></span> }</code>
在单片机刚上电之后,tim_cr1会被设置为TIM1的CR1寄存器的地址,这样做是告诉单片机我们下次进中断需要开启TIM1并在开启TIM1之后为下次进中断开启TIM16做准备,就是把tim_cr1会被设置为TIM16的CR1寄存器的地址。这段代码确保了从进入中断到相应的CR1寄存器最低位被置1(定时器计数使能位)的指令条数完全相等,于是TIM1,TIM16,TIM17会依次在正确的时间被打开,完成三个定时器的同步产生正确的相位差。当TIM17被开启之后,tim_cr1会被置0(标识为无效状态,这样当TIM14作为其他用途用的时候会跳过同步TIM1-17的代码),然后TIM14的也会被禁用。退出中断程序后,while (tim_cr1 > 0); 这里也能够继续执行了。TIM14在同步TIM1,TIM16,TIM17完成之后可以用作其他用途比如执行反馈环的计算等。之后的TIM14中断处理程序写在"} // if(TIM14->SR & TIM_SR_UIF)"这行之后。static void Timer_Sync_1_16_17(void) 的后半段重新配置了TIM14:
<code class="hljs php"><span style="background-color:rgb(245, 245, 245); font-family:Menlo, Monaco, Consolas,;"> </span><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Wait until the synchronization is done</span></span></span></span></span></span></span></span> <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">while</span></span></span></span></span></span></span></span> (tim_cr1 > <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span>); <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Reconfigure timer14 for executing control routine</span></span></span></span></span></span></span></span> TIM14->CR1 = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span>; TIM14->DIER = TIM_DIER_UIE; TIM14->ARR = TIM_ARR_CON; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Auto-reload value : 50kHz overflow</span></span></span></span></span></span></span></span> TIM14->PSC = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span>; TIM14->CNT = <span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number"><span class="hljs-number">0</span></span></span></span></span></span></span></span>; <span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment"><span class="hljs-comment">// Enable the timer again</span></span></span></span></span></span></span></span> TIM14->CR1 |= TIM_CR1_CEN; }</code>
下面三个宏分别是启用PWM输出,禁用PWM输出还有设置占空比:
<code class="hljs ocaml">__STATIC_INLINE void <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_PWM_ENABLE</span></span></span></span></span><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal">()</span></span></span></span></span> { <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM1</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> |= <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM16</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> |= <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM17</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> |= <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; } __STATIC_INLINE void <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_PWM_DISABLE</span></span></span></span></span><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal"><span class="hljs-literal">()</span></span></span></span></span> { <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM1</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> &=~ <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM16</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> &=~ <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM17</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">BDTR</span></span></span></span></span> &=~ <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_BDTR_MOE</span></span></span></span></span>; } __STATIC_INLINE void <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM_PWM_SETVAL</span></span></span></span></span>(uint32_t <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">val</span></span></span></span></span>) { <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM1</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">CCR2</span></span></span></span></span> = <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">val</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM16</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">CCR1</span></span></span></span></span> = <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">val</span></span></span></span></span>; <span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">TIM17</span></span></span></span></span>-><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type"><span class="hljs-type">CCR1</span></span></span></span></span> = <span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword"><span class="hljs-keyword">val</span></span></span></span></span>; }</code>
这个是实验效果:
有的同学可能想问,为啥这么多直接操作寄存器的?全部换成HAL不好吗?我感觉在这种需要对硬件行为进行精确把控的情况下使用HAL是不明智的选择,HAL的实现可能会在函数调用的时候产生短暂的无效输出状态,有可能会导致MOS管的误导通,这对于电源是灾难性的,会booooom
代码在附件里面,HAL库需要手动从Cube里考进来,当然如果把HAL的时钟GPIO初始化换成其他库或者寄存器操作也可以不要HAL。于是大家好好玩233333
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