*(CanNm_Timer[nmChannelHandle].NmTOTimer.TimerCnt)这段代码什么意思

这段代码是访问一个名为CanNm_Timer的数组的第[nmChannelHandle]个元素，该元素是一个结构体类型的变量，其中有一个名为NmTOTimer的成员变量，它又是一个结构体类型的变量，其中有一个名为TimerCnt的成员变量，最终该代码访问的是TimerCnt成员变量的值。因此，这段代码的意思是获取CanNm_Timer数组中第[nmChannelHandle]个元素中NmTOTimer结构体变量中的TimerCnt成员变量的值。

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修改语法 typedef void *TIMER_ID; typedef void (* TAL_TIMER_CB)(void); TIMER_ID zcd_timer; void zcd_callback_func(void) {} unsigned char zero_crossing_detect_unit_sw_timer_create(TAL_TIMER_CB func, void *arg, TIMER_ID *timer_id) { //函数关联的是开启定时器，形参是时间到了执行硬件动作，并且查看是否开启硬件,初始化是开启定时器，并且返回OK if(zero_crossing_detect_unit.zcb_sw_timer_create(zcb_timer_callback, NULL, &zcd_timer) != OPRT_OK) { rt = OPRT_COM_ERROR; } return rt; }

TIMER_ID *timer_id) {
// 初始化定时器并返回OK
zcd_timer = zero_crossing_detect_unit.zcb_sw_timer_create(func, arg, timer_id);
if (zcd_timer != NULL) {
return OK;
} else {
return ERROR;
}
}

// 回调函数
void zcd_callback_func(void) {}

// 定义类型
typedef void *TIMER_ID;
typedef void (*TAL_TIMER_CB)(void);

// 定义变量
TIMER_ID zcd_timer;

// 创建定时器
unsigned char zero_crossing_detect_unit_sw_timer_create(TAL_TIMER_CB func, void *arg, TIMER_ID *timer_id) {
// 调用函数创建定时器
zcd_timer = zero_crossing_detect_unit.zcb_sw_timer_create(func, arg, timer_id);
// 判断定时器是否创建成功
if (zcd_timer != NULL) {
return OK;
} else {
return ERROR;
}
}

void pwm_capture_timer_config(void) { /* TIMER2 configuration: input capture mode ------------------- the external signal is connected to TIMER2 CH0 pin (PB4) the rising edge is used as active edge the TIMER2 CH0CV is used to compute the frequency value ------------------------------------------------------------ */ timer_ic_parameter_struct timer_icinitpara; timer_parameter_struct timer_initpara; rcu_periph_clock_enable(RCU_TIMER0); timer_deinit(TIMER0); /* TIMER1 configuration */ timer_initpara.prescaler = 119; timer_initpara.alignedmode = TIMER_COUNTER_EDGE; timer_initpara.counterdirection = TIMER_COUNTER_UP; timer_initpara.period = 65535; timer_initpara.clockdivision = TIMER_CKDIV_DIV1; timer_initpara.repetitioncounter = 0; timer_init(TIMER0,&timer_initpara); /* TIMER1 configuration */ /* TIMER1 CH2 input capture configuration */ timer_icinitpara.icpolarity = TIMER_IC_POLARITY_FALLING; timer_icinitpara.icselection = TIMER_IC_SELECTION_DIRECTTI; timer_icinitpara.icprescaler = TIMER_IC_PSC_DIV1; timer_icinitpara.icfilter = 0x0; timer_input_capture_config(TIMER0,TIMER_CH_1,&timer_icinitpara); nvic_irq_enable(TIMER0_Channel_IRQn, 1, 1); timer_primary_output_config(TIMER0, ENABLE); /* auto-reload preload enable */ timer_auto_reload_shadow_enable(TIMER0); /* clear channel 0 interrupt bit */ timer_interrupt_flag_clear(TIMER0,TIMER_INT_FLAG_CH1); /* channel 0 interrupt enable */ timer_interrupt_enable(TIMER0,TIMER_INT_CH1); /* TIMER1 counter enable */ timer_enable(TIMER0); }

这是一个针对GD32F305芯片的定时器配置函数，主要是用于输入捕获模式。下面是代码的解释：

1. 开启TIMER0时钟

rcu_periph_clock_enable(RCU_TIMER0);

2. 复位TIMER0

timer_deinit(TIMER0);

3. 配置TIMER0的基本参数，包括计数器方向、计数器分频、计数器模式、计数器周期

timer_parameter_struct timer_initpara;
timer_initpara.prescaler         = 119;
timer_initpara.alignedmode       = TIMER_COUNTER_EDGE;
timer_initpara.counterdirection  = TIMER_COUNTER_UP;
timer_initpara.period            = 65535;
timer_initpara.clockdivision     = TIMER_CKDIV_DIV1;
timer_initpara.repetitioncounter = 0;
timer_init(TIMER0,&timer_initpara);

4. 配置TIMER0的输入捕获通道，包括极性、输入捕获选择、预分频和滤波器参数

timer_ic_parameter_struct timer_icinitpara;
timer_icinitpara.icpolarity  = TIMER_IC_POLARITY_FALLING;
timer_icinitpara.icselection = TIMER_IC_SELECTION_DIRECTTI;
timer_icinitpara.icprescaler = TIMER_IC_PSC_DIV1;
timer_icinitpara.icfilter    = 0x0;
timer_input_capture_config(TIMER0,TIMER_CH_1,&timer_icinitpara);

5. 配置TIMER0的中断

nvic_irq_enable(TIMER0_Channel_IRQn, 1, 1);
timer_primary_output_config(TIMER0, ENABLE);
/* auto-reload preload enable */     
timer_auto_reload_shadow_enable(TIMER0);
/* clear channel 0 interrupt bit */     
timer_interrupt_flag_clear(TIMER0,TIMER_INT_FLAG_CH1);
/* channel 0 interrupt enable */     
timer_interrupt_enable(TIMER0,TIMER_INT_CH1);

6. 开启TIMER0计数

timer_enable(TIMER0);

总体来说，这个函数的作用是配置TIMER0为输入捕获模式，其中TIMER0的计数器值会根据外部信号的变化而变化，以实现计时和计数等功能。其中的nvic_irq_enable函数是用于使能TIMER0的中断，timer_interrupt_enable函数是用于使能TIMER0的输入捕获通道中断。需要注意的是，这个函数只是一个配置函数，需要在调用时传入相应的参数才能实现具体的功能。