STM32f072 定时1MS配置

### STM32F072 1ms Timer Configuration Example Code and Tutorial

For configuring a 1 millisecond (ms) timer on the STM32F072 microcontroller, one can utilize the built-in timers such as TIM6 or TIM7 which are basic timers suitable for timing applications without input capture/output compare functionalities. The configuration involves setting up the prescaler and period values to achieve the desired time base of 1 ms.

The formula relating these parameters is given by:

\[ \text{Period} (\mu s) = \left(\frac{\text{Prescaler Value}}{\text{APB Clock Frequency}(MHz)}\right)(\text{Auto Reload Register Value} + 1) \]

To set this up for a 1 ms interval when using an APB clock frequency of \(f_{clk}\), rearrange it accordingly[^1]:

Given that the goal is to generate interrupts every 1 ms with respect to the system's core clock speed, here’s how to configure TIM6 for generating periodic updates at intervals corresponding to 1 ms duration:

#### Hardware Initialization Function

#include "stm32f0xx_hal.h"

// Assuming SystemCoreClock has been properly initialized elsewhere.
static void MX_TIM6_Init(void)
{
    __HAL_RCC_TIM6_CLK_ENABLE();

    TIM_HandleTypeDef htim6;
    
    htim6.Instance = TIM6;

    // Prescaler value calculation based on required resolution; assuming SysClk=48 MHz,
    // we want each tick to represent approximately 1 us -> PreScaler=(SysClk/1us)-1
    uint32_t uwPrescalerValue = ((SystemCoreClock / 1000000U) - 1U);
  
    htim6.Init.Prescaler         = uwPrescalerValue;
    htim6.Init.CounterMode       = TIM_COUNTERMODE_UP;
    htim6.Init.Period            = 999;          /* To get exactly 1 ms */
    htim6.Init.ClockDivision     = TIM_CLOCKDIVISION_DIV1;
    htim6.Init.AutoReloadPreload = TIM_AUTORELOAD_PRELOAD_DISABLE;
   
    HAL_TIM_Base_Init(&htim6);

    // Enable interrupt generation upon update event completion
    HAL_TIM_Base_Start_IT(&htim6);
}

This function initializes TIM6 so that its counter overflows after counting from 0 through `ARR` register value within about 1 ms depending on the chosen prescaler settings. An interrupt service routine should also be defined to handle actions once the specified amount of time elapses.

#### Interrupt Service Routine Definition

extern "C" {
void TIM6_DAC_IRQHandler(void){
    HAL_TIM_IRQHandler(&htim6); 
}}

Ensure proper linkage between hardware abstraction layer functions provided by STMicroelectronics' CubeMX toolchain or equivalent setup method used during project development phase.

--related questions--

1. How does changing the prescaler affect the accuracy of the generated pulse width modulation signal?
2. What considerations must be taken into account while selecting different types of timers available in STM32 series devices like general-purpose versus advanced-control ones?
3. Can you explain more about handling multiple peripherals sharing same IRQ lines efficiently in embedded systems programming context?