用HAL库编写一个让LCD1602显示数字的头文件和源文件

以下是使用STM32的HAL库编写一个让LCD1602显示数字的头文件和源文件的示例：

头文件 `lcd1602.h`

#ifndef __LCD1602_H
#define __LCD1602_H

#include "stm32f1xx_hal.h"

#define LCD_CMD_CLEAR_DISPLAY         0x01
#define LCD_CMD_RETURN_HOME           0x02
#define LCD_CMD_ENTRY_MODE_SET        0x04
#define LCD_CMD_DISPLAY_CONTROL       0x08
#define LCD_CMD_CURSOR_SHIFT          0x10
#define LCD_CMD_FUNCTION_SET          0x20
#define LCD_CMD_SET_CGRAM_ADDRESS     0x40
#define LCD_CMD_SET_DDRAM_ADDRESS     0x80

#define LCD_CMD_DISPLAY_ON            0x04
#define LCD_CMD_DISPLAY_OFF           0x00
#define LCD_CMD_CURSOR_ON             0x02
#define LCD_CMD_CURSOR_OFF            0x00
#define LCD_CMD_BLINK_ON              0x01
#define LCD_CMD_BLINK_OFF             0x00

void LCD_Init(I2C_HandleTypeDef *hi2c);
void LCD_SendCommand(uint8_t cmd);
void LCD_SendData(uint8_t data);
void LCD_SendString(char *str);
void LCD_SetCursor(uint8_t row, uint8_t col);
void LCD_DisplayNumber(uint16_t num);

#endif /* __LCD1602_H */

源文件 `lcd1602.c`

#include "lcd1602.h"

#define LCD_I2C_ADDRESS     0x4E

static I2C_HandleTypeDef *hi2c;

void LCD_Init(I2C_HandleTypeDef *hi2c_handle)
{
    hi2c = hi2c_handle;

    // Wait for LCD to become ready
    HAL_Delay(50);

    // Initialize LCD in 4-bit mode
    LCD_SendCommand(0x33);
    LCD_SendCommand(0x32);
    LCD_SendCommand(LCD_CMD_FUNCTION_SET | 0x08);
    LCD_SendCommand(LCD_CMD_DISPLAY_CONTROL | LCD_CMD_DISPLAY_OFF);
    LCD_SendCommand(LCD_CMD_CLEAR_DISPLAY);
    LCD_SendCommand(LCD_CMD_ENTRY_MODE_SET | 0x04);
    LCD_SendCommand(LCD_CMD_DISPLAY_CONTROL | LCD_CMD_DISPLAY_ON | LCD_CMD_CURSOR_OFF | LCD_CMD_BLINK_OFF);
}

void LCD_SendCommand(uint8_t cmd)
{
    uint8_t data[4];

    data[0] = (cmd & 0xF0) | 0x04;  // RS = 0, EN = 1
    data[1] = (cmd & 0xF0) | 0x00;  // RS = 0, EN = 0
    data[2] = ((cmd << 4) & 0xF0) | 0x04;  // RS = 0, EN = 1
    data[3] = ((cmd << 4) & 0xF0) | 0x00;  // RS = 0, EN = 0

    HAL_I2C_Master_Transmit(hi2c, LCD_I2C_ADDRESS, data, 4, 100);
    HAL_Delay(1);
}

void LCD_SendData(uint8_t data)
{
    uint8_t lcd_data[4];

    lcd_data[0] = (data & 0xF0) | 0x05;  // RS = 1, EN = 1
    lcd_data[1] = (data & 0xF0) | 0x01;  // RS = 1, EN = 0
    lcd_data[2] = ((data << 4) & 0xF0) | 0x05;  // RS = 1, EN = 1
    lcd_data[3] = ((data << 4) & 0xF0) | 0x01;  // RS = 1, EN = 0

    HAL_I2C_Master_Transmit(hi2c, LCD_I2C_ADDRESS, lcd_data, 4, 100);
    HAL_Delay(1);
}

void LCD_SendString(char *str)
{
    while (*str)
        LCD_SendData((uint8_t)*str++);
}

void LCD_SetCursor(uint8_t row, uint8_t col)
{
    uint8_t address;

    if (row == 0)
        address = col;
    else
        address = col + 0x40;

    LCD_SendCommand(LCD_CMD_SET_DDRAM_ADDRESS | address);
}

void LCD_DisplayNumber(uint16_t num)
{
    char buffer[5];
    sprintf(buffer, "%d", num);
    LCD_SendString(buffer);
}

这个示例代码使用了I2C通信协议，需要连接STM32的I2C总线和LCD1602的I2C接口。在使用这个库时，需要提供一个`I2C_HandleTypeDef`类型的指针作为传输参数。