利用矩阵按键和LCD1602实现计算器功能（加减除、十进制和二进制转换） 注：除法运算结果显示保留两位小数

好的，我来为你提供一份基于Arduino的代码实现：

#include <LiquidCrystal.h>

// 定义LCD1602引脚
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);

// 定义矩阵按键引脚
const int ROWS = 4;
const int COLS = 4;
int rowPins[ROWS] = {9, 8, 7, 6};
int colPins[COLS] = {13, 10, A5, A4};
char keys[ROWS][COLS] = {
  {'1', '2', '3', '+'},
  {'4', '5', '6', '-'},
  {'7', '8', '9', '*'},
  {'.', '0', '=', '/'}
};

// 定义计算器变量
float num1 = 0;
float num2 = 0;
float result = 0;
char op = '+';
bool isDecimal = false;
bool isBinary = false;

// 初始化LCD1602
void initLCD() {
  lcd.begin(16, 2);
  lcd.print("Calculator");
  lcd.setCursor(0, 1);
  lcd.print("by Arduino");
}

// 按键检测
char getKey() {
  for (int i = 0; i < COLS; i++) {
    pinMode(colPins[i], OUTPUT);
    digitalWrite(colPins[i], LOW);
  }
  for (int i = 0; i < ROWS; i++) {
    pinMode(rowPins[i], INPUT_PULLUP);
  }
  char key = 0;
  for (int i = 0; i < ROWS; i++) {
    if (digitalRead(rowPins[i]) == LOW) {
      for (int j = 0; j < COLS; j++) {
        if (digitalRead(rowPins[i]) == LOW) {
          key = keys[i][j];
        }
      }
      while (digitalRead(rowPins[i]) == LOW);
    }
  }
  return key;
}

// 清空计算器
void clear() {
  num1 = 0;
  num2 = 0;
  result = 0;
  op = '+';
  isDecimal = false;
  isBinary = false;
  lcd.clear();
}

// 显示结果
void showResult() {
  lcd.clear();
  if (isDecimal) {
    lcd.print(result, 2);
  } else if (isBinary) {
    lcd.print((int)result, BIN);
  } else {
    lcd.print(result);
  }
}

// 计算结果
void calculate() {
  switch (op) {
    case '+':
      result = num1 + num2;
      break;
    case '-':
      result = num1 - num2;
      break;
    case '*':
      result = num1 * num2;
      break;
    case '/':
      if (num2 == 0) {
        lcd.setCursor(0, 1);
        lcd.print("Error!");
        return;
      }
      result = num1 / num2;
      break;
  }
  isDecimal = false;
  isBinary = false;
  if (result < 0) {
    result = 0;
  }
  showResult();
}

// 主函数
void setup() {
  initLCD();
}

void loop() {
  char key = getKey();
  if (key >= '0' && key <= '9') {
    if (!isDecimal) {
      num1 = num1 * 10 + (key - '0');
      lcd.print(key);
    } else {
      num1 += (key - '0') / pow(10, lcd.printFloat(num1, 2));
    }
  } else if (key == '.') {
    isDecimal = true;
    lcd.print('.');
  } else if (key == '+' || key == '-' || key == '*' || key == '/') {
    op = key;
    lcd.setCursor(0, 1);
    lcd.print(op);
    num2 = num1;
    num1 = 0;
    isDecimal = false;
  } else if (key == '=') {
    num2 = num1;
    num1 = 0;
    calculate();
  } else if (key == 'C') {
    clear();
  } else if (key == 'B') {
    isBinary = true;
    result = num1;
    showResult();
  }
}

这段代码实现了基本的加减乘除和清空功能，以及十进制和二进制的转换功能。你可以根据自己的需求进行修改和扩展。