LCD
目录
- Arduino API
- Arduino UNO R3
- STM32F103C8T6 Bule Pill
- ESP32-DevKitC
- MicroPython API
- STM32Cube（待补充）
Arduino API
Arduino UNO R3
/*
LCD I2C Example - 16x2 Display
This example demonstrates how to control a 16x2 LCD using the I2C protocol with Arduino.
It prints "Hello world!" on the first row and "LCD Tutorial" on the second row.
Circuit:
- An I2C LCD display is connected to the Arduino.
Diagram:
Arduino I2C LCD
------------------------
| 5V | --> | VCC |
| GND | --> | GND |
| A4 | --> | SDA |
| A5 | --> | SCL |
------------------------
created 2024
by Liang
*/
#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library for controlling the LCD
// Initialize the LCD with address 0x20, 16 columns, and 2 rows
// The first parameter is the I2C address (0x20 in this case)
// The second and third parameters specify that it is a 16x2 LCD
LiquidCrystal_I2C lcd(0x20, 16, 2);
void setup()
{
lcd.init(); // Initialize the LCD, setting it up for use
lcd.clear(); // Clear the LCD screen to ensure it's empty
lcd.backlight(); // Turn on the LCD backlight
// Print a message on the first row of the LCD
lcd.setCursor(2, 0); // Set the cursor to column 2 of row 0 (first row)
lcd.print("Hello world!"); // Print "Hello world!" on the first row
// Print a message on the second row of the LCD
lcd.setCursor(2, 1); // Move the cursor to column 2 of row 1 (second row)
lcd.print("LCD Tutorial"); // Print "LCD Tutorial" on the second row
}
void loop()
{
// No operation needed in loop for this simple example
// The messages on the LCD will remain static
}
STM32F103C8T6 Bule Pill
/*
LCD I2C Example - 16x2 Display for STM32F103C8T6 (Blue Pill)
This example demonstrates how to control a 16x2 LCD using the I2C protocol with STM32F103C8T6.
It prints "Hello world!" on the first row and "LCD Tutorial" on the second row.
Circuit:
- An I2C LCD display is connected to the STM32F103C8T6.
Diagram:
STM32F103C8T6 I2C LCD
------------------------------
| 5V | ------> | VCC |
| GND | ------> | GND |
| PB7 | ------> | SDA |
| PB6 | ------> | SCL |
-----------------------------
created 2024
by Liang
*/
#include <Wire.h> // Include Wire library for I2C
#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library for controlling the LCD
// Initialize the LCD with the I2C address (0x20), 16 columns, and 2 rows
LiquidCrystal_I2C lcd(0x20, 16, 2);
void setup() {
lcd.init(); // Initialize the LCD
lcd.clear(); // Clear the LCD screen
lcd.backlight(); // Turn on the LCD backlight
// Print a message on the first row of the LCD
lcd.setCursor(2, 0); // Set cursor to column 2 of row 0 (first row)
lcd.print("Hello world!"); // Print "Hello world!" on the first row
// Print a message on the second row of the LCD
lcd.setCursor(2, 1); // Move cursor to column 2 of row 1 (second row)
lcd.print("LCD Tutorial"); // Print "LCD Tutorial" on the second row
}
void loop() {
// No operation needed in loop for this example
}
ESP32-DevKitC
/*
LCD I2C Example - 16x2 Display for ESP32
This example demonstrates how to control a 16x2 LCD using the I2C protocol with ESP32.
It prints "Hello world!" on the first row and "LCD Tutorial" on the second row.
Circuit:
- An I2C LCD display is connected to the ESP32.
Diagram:
ESP32 I2C LCD
--------------------------
| 3.3V/5V | ---> | VCC |
| GND | ---> | GND |
| GPIO 21 | ---> | SDA |
| GPIO 22 | ---> | SCL |
----------------------------
created 2024
by Liang
*/
#include <Wire.h> // Include the Wire library for I2C
#include <LiquidCrystal_I2C.h> // Include the LiquidCrystal_I2C library for controlling the LCD
// Initialize the LCD with the I2C address (0x20), 16 columns, and 2 rows
LiquidCrystal_I2C lcd(0x20, 16, 2);
void setup() {
lcd.init(); // Initialize the LCD
lcd.clear(); // Clear the LCD screen
lcd.backlight(); // Turn on the LCD backlight
// Print a message on the first row of the LCD
lcd.setCursor(2, 0); // Set cursor to column 2 of row 0 (first row)
lcd.print("Hello world!"); // Print "Hello world!" on the first row
// Print a message on the second row of the LCD
lcd.setCursor(2, 1); // Move cursor to column 2 of row 1 (second row)
lcd.print("LCD Tutorial"); // Print "LCD Tutorial" on the second row
}
void loop() {
// No operation needed in loop for this example
}
MicroPython API
ESP32-DevKitC
"""
LCD I2C示例 - 16x2显示屏
此示例展示了如何使用ESP32-DevKitC并基于MicroPython框架通过I2C协议控制一个16x2的LCD显示屏。
它会在LCD的第一行显示“Hello world!”，在第二行显示“LCD Tutorial”。
电路连接情况：
- 一个I2C接口的LCD显示屏连接到ESP32-DevKitC开发板。
连接示意图如下：
ESP32-DevKitC I2C LCD
------------------------
| 3.3V | --> | VCC |
| GND | --> | GND |
| 21 | --> | SDA |
| 22 | --> | SCL |
------------------------
注：在ESP32-DevKitC中，通常使用引脚21作为SDA（数据信号线），引脚22作为SCL（时钟信号线）来进行I2C通信，这里的引脚与Arduino有所不同。
创建于2024
作者：Liang
"""
from machine import Pin, I2C
import time
from lcd_api import LcdApi
from i2c_lcd import I2cLcd
# I2C对象初始化，指定SDA引脚为21，SCL引脚为22，波特率为100000（这是I2C常用的标准波特率）
i2c = I2C(scl=Pin(22), sda=Pin(21), freq=100000)
# 扫描I2C总线上的设备，获取设备地址列表，一般情况下，我们期望找到的LCD设备地址在这里获取到
devices = i2c.scan()
if len(devices) == 0:
print("没有发现I2C设备，请检查硬件连接")
else:
print("发现I2C设备地址:", devices)
# 假设LCD的I2C地址为0x27（不同的LCD模块地址可能不同，需要根据实际情况修改，此处示例假设为0x27）
lcd_address = 0x27
# 初始化LCD对象，传入I2C对象、设备地址、行数和列数信息，这里是16列2行的LCD
lcd = I2cLcd(i2c, lcd_address, 2, 16)
def setup_lcd():
"""
初始化LCD显示相关设置的函数。
此函数用于清空LCD屏幕、打开背光，并在相应位置显示指定的文本内容。
"""
lcd.clear() # 清空LCD屏幕，确保初始状态下屏幕上没有残留内容
lcd.backlight_on() # 打开LCD的背光，使屏幕能够正常显示内容
# 设置光标位置到第一行第2列（行列计数从0开始）
lcd.move_to(2, 0)
lcd.putstr("Hello world!") # 在第一行显示"Hello world!"
# 设置光标位置到第二行第2列
lcd.move_to(2, 1)
lcd.putstr("LCD Tutorial") # 在第二行显示"LCD Tutorial"
setup_lcd()
while True:
"""
主循环，由于这个示例只是简单显示固定文本，所以循环内暂时无需额外操作。
如果后续需要更新显示内容等，可以在这个循环内添加相应逻辑代码。
"""
time.sleep(1) # 适当延时，避免程序空转占用过多资源，这里每秒延时一次，可根据实际情况调整