物联网开发111 - Micropython ESP32 C3连接4x4矩阵按键模块操作

一、目的

        这一节我们来学习如何使用合宙ESP32 C3，连接0.96寸ssd1306屏幕、4x4 矩阵按键模块，进行两个小实验的演示。

二、环境

        ESP32 C3开发板（MicroPython v1.19.1 on 2022-06-18）+ I2C 0.96寸ssd1306屏幕模块+ 4x4 矩阵按键模块  + 几根杜邦线 + Win10商业版

        ESP32 C3和各个模块接线方法：

 三、示例代码1

演示将按下的按键名字显示在屏幕上

from machine import Pin,I2C
from ssd1306 import SSD1306_I2C
from ufont import BMFont
import time

# 创建I2C对象
i2c  = I2C(0,scl = Pin(5),sda = Pin(4),freq = 400_000)
# 创建oled屏幕对象
oled = SSD1306_I2C(128,64,i2c,0x3c)
# 定义字库文件
font = BMFont("fonts/unifont-14-12888-16.v3.bmf")
# 创建led对象
led = Pin(12,Pin.OUT)  # 板载led D4

# 行定义
R1 = Pin( 2,Pin.OUT)
R2 = Pin( 3,Pin.OUT)
R3 = Pin(10,Pin.OUT)
R4 = Pin( 6,Pin.OUT)

# 列第一
C1 = Pin( 7,Pin.IN,Pin.PULL_UP)
C2 = Pin( 8,Pin.IN,Pin.PULL_UP)
C3 = Pin(18,Pin.IN,Pin.PULL_UP)
C4 = Pin(19,Pin.IN,Pin.PULL_UP)

# 创建按键函数
def Key():
    
#     R1.value(0)
#     R2.value(1)
#     R3.value(1)
#     R4.value(1)
    
    key = 0
    bzw = 0
    
    # 第一行
    [R1.value(0),R2.value(1),R3.value(1),R4.value(1)]
    if(C1.value() == 0 or C2.value() == 0 or C3.value() == 0 or C4.value() == 0):
        
        time.sleep(0.020)
        
        if C1.value() == 0:
            bzw = 1
            key = 0
            while not C1.value():
                None
        elif C2.value() == 0:
            bzw = 1
            key = 1
            while not C2.value():
                None               
        elif C3.value() == 0:
            bzw = 1
            key = 2
            while not C3.value():
                None
        elif C4.value() == 0:
            bzw = 1
            key = 3
            while not C4.value():
                None
        else:
            
            key = 0
            bzw = 0
            R1.value(1)
            
    # 第二行
    [R1.value(1),R2.value(0),R3.value(1),R4.value(1)]
    if(C1.value() == 0 or C2.value() == 0 or C3.value() == 0 or C4.value() == 0):
        
        time.sleep(0.020)
        
        if C1.value() == 0:
            bzw = 1
            key = 4
            while not C1.value():
                None
        elif C2.value() == 0:
            bzw = 1
            key = 5
            while not C2.value():
                None               
        elif C3.value() == 0:
            bzw = 1
            key = 6
            while not C3.value():
                None
        elif C4.value() == 0:
            bzw = 1
            key = 7
            while not C4.value():
                None
        else:
            
            key = 0
            bzw = 0
            R1.value(1)
            
    # 第三行
    [R1.value(1),R2.value(1),R3.value(0),R4.value(1)]
    if(C1.value() == 0 or C2.value() == 0 or C3.value() == 0 or C4.value() == 0):
        
        time.sleep(0.020)
        
        if C1.value() == 0:
            bzw = 1
            key = 8
            while not C1.value():
                None
        elif C2.value() == 0:
            bzw = 1
            key = 9
            while not C2.value():
                None               
        elif C3.value() == 0:
            bzw = 1
            key = 10
            while not C3.value():
                None
        elif C4.value() == 0:
            bzw = 1
            key = 11
            while not C4.value():
                None
        else:
            
            key = 0
            bzw = 0
            R1.value(1)

    # 第四行
    [R1.value(1),R2.value(1),R3.value(1),R4.value(0)]
    if(C1.value() == 0 or C2.value() == 0 or C3.value() == 0 or C4.value() == 0):
        
        time.sleep(0.020)
        
        if C1.value() == 0:
            bzw = 1
            key = 12
            while not C1.value():
                None
        elif C2.value() == 0:
            bzw = 1
            key = 13
            while not C2.value():
                None               
        elif C3.value() == 0:
            bzw = 1
            key = 14
            while not C3.value():
                None
        elif C4.value() == 0:
            bzw = 1
            key = 15
            while not C4.value():
                None
        else:
            
            key = 0
            bzw = 0
            R1.value(1)


    if bzw == 1:
        bzw = 0
        
        if key == 3:
            led.value(not led.value())
            
        print("%d"%key)
        font.text(oled,&#