Question

我已经编写了一些代码来显示转向信号的箭头。我正在尝试实现一个两个按钮系统，决定显示哪个方向箭头。我有两个问题。

8x8 LED矩阵因打开而开始，我无法弄清楚原因。
当我按下左按钮时，它会停止箭头。

我没有包含LED绘制箭头的代码，因为它只包含填充每个帧速率的数组。

#include "LedControl.h"

/*the last is how many matrices you have connected (dataPin, clockPin, 
csPin, numberDevices) */
LedControl lc = LedControl(12, 11, 10, 1);
int lButton = 2, rButton = 3, lButtonState = 0, rButtonState = 0;


void setup() {
    pinMode(lButton, INPUT);
    pinMode(rButton, INPUT);
}


void leftArrow(){
    //in setup everything is done once
    /*
    The MAX7219 is in power-saving mode on startup,
    we have to do a wakeup call
    */
    lc.shutdown(0, false);
    // Set the brightness to a medium value
    lc.setIntensity(0, 8);
    // and clear the display
    lc.clearDisplay(0);
}

void loop() {
    lButtonState = digitalRead(lButton);
    if (lButtonState == HIGH)
        leftArrow();
}

Answer 1

1_检查您的电路连接。他们可能在数据或 CLK 引脚上有问题

2_要解决void loop()中的箭头问题，还必须加上else，如果不按下，会显示别的东西或者关掉什么的...

void loop(){
    lButtonState = digitalRead(lButton);
    rButtonState = digitalRead(rButton);
    if (lButtonState == HIGH){
       leftArrow();
    }
    else if (rButtonState == HIGH){
       rightArrow();
    }
    else {
      lc.clearDisplay(0);
    }

8x8 LED矩阵和按钮

1 个答案: