【目的】實現一個計數器，按下按鍵1開始計時，再次按下按鍵1實現暫停，再次按下，繼續計時。按下按鍵2實現清零。

【實現步驟】

1、初始化時鐘，代碼如下：

void RCC_Configuration(void)

{

/* 0. HSI使能并校準 */

// RCC_HSI_OUT();

RCC_HSI_Enable(RCC_HSIOSC_DIV6);

/* 1. 設置HCLK和PCLK的分頻系數 */

RCC_HCLKPRS_Config(RCC_HCLK_DIV1);

RCC_PCLKPRS_Config(RCC_PCLK_DIV1);

// RCC_HCLK_OUT();

// __breakpoint(0);

/* 2. 使能PLL，通過HSI倍頻到64MHz */

RCC_PLL_Enable(RCC_PLLSOURCE_HSI, 8000000, RCC_PLL_MUL_8); // HSI 默認輸出頻率8MHz

// RCC_PLL_OUT();

///< 當使用的時鐘源HCLK大于24M,小于等于48MHz：設置FLASH 讀等待周期為2 cycle

///< 當使用的時鐘源HCLK大于48M,小于等于72MHz：設置FLASH 讀等待周期為3 cycle

__RCC_FLASH_CLK_ENABLE();

FLASH_SetLatency(FLASH_Latency_3);

/* 3. 時鐘切換到PLL */

RCC_SysClk_Switch(RCC_SYSCLKSRC_PLL);

RCC_SystemCoreClockUpdate(64000000);

/* 4. 配置外設時鐘 */

// __RCC_GPIOF_CLK_ENABLE();

// __RCC_GPIOE_CLK_ENABLE();

// __RCC_GPIOD_CLK_ENABLE();

// __RCC_GPIOC_CLK_ENABLE();

// __RCC_GPIOB_CLK_ENABLE();

// __RCC_GPIOA_CLK_ENABLE();

// __RCC_LCD_CLK_ENABLE();

}

2. 初始化按鍵

板載按鍵1為PA4,按鍵2為PA5，根據原理圖，都接了上位電阻，所以需要配置為下拉中斷觸發。

void GPIO_Configuration(void)

{

GPIO_InitTypeDef GPIO_InitStruct = {0};

/* 配置PA4、PA5為按鍵輸入 */

GPIO_InitStruct.IT = GPIO_IT_FALLING;

GPIO_InitStruct.Mode = GPIO_MODE_INPUT;

GPIO_InitStruct.Pins = GPIO_PIN_4 | GPIO_PIN_5;

__RCC_GPIOA_CLK_ENABLE();

GPIO_Init(CW_GPIOA, &GPIO_InitStruct);

}

3、中斷配置

void NVIC_Configuration(void)

{

__disable_irq();

// NVIC_EnableIRQ(WDT_IRQn);

NVIC_SetPriority(GPIOA_IRQn, 0);

// NVIC_SetPriority(SysTick_IRQn, 1);

NVIC_EnableIRQ(GPIOA_IRQn);

__enable_irq();

}

4、中斷回調函數，在中斷回調中只清除中斷標志，業務處理在主函數中處理：

/**

• @brief This funcation handles GPIOA
  */
  void GPIOA_IRQHandler(void)
  {

CW_GPIOA->ICR = 0; //清除中斷標志

}

5、LCD驅動

在LCD驅動中，我們初始化LCD（具體見官方示例），然后是書寫LCD數字顯示驅動，具體代碼如下：

#include "lcd.h"

// 7 6 5 4 3 2 1 0

// RAM01 RAM00 RAM03 RAM02 RAM801 RAM10 RAM13 RAM12 RAM92 RAM91

/* 段碼低8（左） */

static uint8_t num_L[10] = {

0x0d, //0

0x00, //1

0x0e, //2

0x0a, //3

0x03, //4

0x0b, //5

0x0f, //6

0x00, //7

0x0f, //8

0x0b, //9

};

/* 段碼高8（右） */

static uint8_t num_H[10] = {

0x07,

0x06,

0x03,

0x07,//3

0x06,//4

0x05, //5

0x05, //

0x07, //7

0x07, //8

0x07, //9

};

void show_nums(uint32_t num)

{

uint8_t i=0;

uint8_t j;

uint32_t temp;

temp = num;

//空顯示

CW_LCD->RAM0 = 0;

CW_LCD->RAM1 = 0;

CW_LCD->RAM8 = 0;

CW_LCD->RAM9 = 0;

if(temp == 0)

show_num(0,0);

while(temp>0)

{

j = temp%10;

show_num(i,j);

temp /=10;

i++;

}

}

void show_num(uint8_t wei, uint8_t num)

{

switch(wei)

{

case 7:

{

//顯示第7個數碼管

CW_LCD->RAM0 |= num_H[num]<<8 | num_L[num];

break;

}

case 6:

{

//顯示第6個數碼管

CW_LCD->RAM0 |= (num_H[num]<<8 | num_L[num]) <<16;

break;

}

case 5:

{

//顯示第5個數碼管

CW_LCD->RAM1 |= num_L[num];

CW_LCD->RAM8 |= num_H[num];

break;

}

case 4:

{

//顯示第4個數碼管

CW_LCD->RAM8 |= num_H[num]<<16 | num_L[num]<<8;

break;

}

case 3:

{

//顯示第3個數碼管

CW_LCD->RAM8 |= num_L[num]<<24;

CW_LCD->RAM9 |= num_H[num];

break;

}

case 2:

{

//顯示第2個數碼管

CW_LCD->RAM9 |= num_H[num]<<16 | num_L[num]<<8;

break;

}

case 1:

{

//顯示第1個數碼管

CW_LCD->RAM1 |= num_H[num]<<8;

CW_LCD->RAM9 |= num_L[num]<<24;

break;

}

case 0:

{

//顯示第0個數碼管

CW_LCD->RAM1 |= num_H[num]<<24 | num_L[num]<<16;

break;

}

}

}

void LCD_Configuration(void)

{

LCD_InitTypeDef LCD_InitStruct = {0};

LCD_InitStruct.LCD_Bias = LCD_Bias_1_3;

LCD_InitStruct.LCD_ClockSource = LCD_CLOCK_SOURCE_LSI;

LCD_InitStruct.LCD_Duty = LCD_Duty_1_4;

LCD_InitStruct.LCD_ScanFreq = LCD_SCAN_FREQ_256HZ;

LCD_InitStruct.LCD_VoltageSource = LCD_VoltageSource_Internal;

__RCC_LCD_CLK_ENABLE();

RCC_LSI_Enable();

LCD_Init(&LCD_InitStruct); //基本配置

// BTL004 LCD 對應的連接

//PA12 COM3

//PA11 COM2

//PA10 COM1

//PA09 COM0

//PA08 SEG0

//PC09 SEG1

//PC08 SEG2

//PC07 SEG3

//PC06 SEG4

//PD15 SEG32

//PD14 SEG33

//PD13 SEG34

//PD12 SEG35

//PD11 SEG36

//PD10 SEG37

//PD09 SEG38

//PD08 SEG39

//PB15 SEG5

//PB14 SEG6

//PB13 SEG7

// 分配引腳

LCD_COMConfig(LCD_COM0 | LCD_COM1 | LCD_COM2 | LCD_COM3, ENABLE);

LCD_SEG0to23Config(0x0000FF, ENABLE);

LCD_SEG32to55Config(0x0000FF,ENABLE);

CW_LCD->RAM[0] = 0;

CW_LCD->RAM[1] = 0;

CW_LCD->RAM2 = 0;

CW_LCD->RAM3 = 0;

CW_LCD->RAM4 = 0;

CW_LCD->RAM5 = 0;

CW_LCD->RAM6 = 0;

CW_LCD->RAM7 = 0;

CW_LCD->RAM8 = 0;

CW_LCD->RAM9 = 0;

CW_LCD->RAM10 = 0;

CW_LCD->RAM11 = 0;

CW_LCD->RAM12 = 0;

CW_LCD->RAM13 = 0;

LCD_Cmd(ENABLE);

CW_LCD->RAM0 = 0x0f0f;

LCD_ContrastConfig(LCD_Contrast_Level_2);

LCD_DriveVoltageConfig(LCD_INRS_LEVEL_0);

}

5、主函數中，我們檢查按鍵1、按鍵2，并做出相應的處理。具體代碼如下：

#include "main.h"

void NVIC_Configuration(void);

void RCC_Configuration(void);

uint8_t Key1Count = 0;

uint8_t Key2Count = 0;

int32_t main(void)

{

uint32_t show_conut=0;

uint32_t time_count = 0;

CW_SYSCTRL->AHBEN_f.GPIOC = 1U; //Open GPIOA Clk

CW_GPIOC->ANALOG_f.PIN2 = 0U; //Digital

CW_GPIOC->BRR_f.BRR2 = 1U; //Reset PA00

CW_GPIOC->DIR_f.PIN2 = 0U; //Output

RCC_Configuration();

GPIO_Configuration();

NVIC_Configuration();

LCD_Configuration();

show_nums(show_conut);

while(1)(//file1.elecfans.com/web2/M00/8A/01/wKgaomSOTM-AOJUkAAWbBlv4TTM763.zip)

{

if(PA04_GETVALUE() == 0)

{

FirmwareDelay( 20000 );

if(PA04_GETVALUE() == 0)

{

Key1Count++;

}

}

if(PA05_GETVALUE() == 0)

{

FirmwareDelay( 20000 );

if(PA05_GETVALUE() == 0)

{

Key2Count++;

}

}

//如果按下2暫停顯示

if(Key1Count == 2 )

{

Key1Count=0;

}

//按下K2清零,停止顯示

if(Key2Count==1)

{

show_conut = 0;

Key1Count = 0;

Key2Count = 0;

show_nums(show_conut);

}

FirmwareDelay( 200 );

time_count ++;

if(time_count > 1000)

{

time_count = 1;

//如果按下1開始顯示

if(Key1Count ==1)

{

show_conut ++;

show_nums(show_conut);

}

//溢出清零

if(show_conut==65535)

{

show_conut=0;

}

//翻轉LED1

CW_GPIOC->TOG = bv2;

}

}

}