基于arduino mega2560设计一个代码。当电路同上电时，电机没有启动，许按下启动按键电机才能启动，通过控制两个继电器控制一个电机正反转，正转运行120s，暂停600s，再反转120s，再通过数码管显示电流值，电流保护值，正转时间，反转时间，暂停时间，并且保护电流值，正转时间，反转时间，暂停时间，可以通过按键调整。要求不使用tm1640的

以下是基于Arduino Mega2560的代码，实现了上述要求：

#define motorPin1 22  // 电机正转控制继电器引脚
#define motorPin2 24  // 电机反转控制继电器引脚
#define startButtonPin 26  // 启动按键引脚
#define currentSensorPin A0  // 电流传感器引脚

// 数码管引脚定义
#define digit1 30
#define digit2 32
#define digit3 34
#define digit4 36
#define segmentA 31
#define segmentB 33
#define segmentC 35
#define segmentD 37
#define segmentE 39
#define segmentF 41
#define segmentG 43
#define segmentDP 45

int motorState = 0;  // 电机状态，0表示停止，1表示正转，2表示反转
unsigned long startTime = 0;  // 记录电机启动时间
unsigned long stopTime = 0;  // 记录电机停止时间
unsigned long pauseTime = 0;  // 记录电机暂停时间
unsigned long currentTime = 0;  // 当前时间
float current = 0;  // 电流值
float currentThreshold = 1.0;  // 电流保护值
unsigned long forwardTime = 120000;  // 正转时间，单位ms
unsigned long backwardTime = 120000;  // 反转时间，单位ms
unsigned long pauseDuration = 600000;  // 暂停时间，单位ms

// 数码管显示的数码值
int digit1_val = 0;
int digit2_val = 0;
int digit3_val = 0;
int digit4_val = 0;

void setup() {
  pinMode(motorPin1, OUTPUT);
  pinMode(motorPin2, OUTPUT);
  pinMode(startButtonPin, INPUT_PULLUP);
  pinMode(currentSensorPin, INPUT);
  
  // 数码管引脚设置为输出
  pinMode(digit1, OUTPUT);
  pinMode(digit2, OUTPUT);
  pinMode(digit3, OUTPUT);
  pinMode(digit4, OUTPUT);
  pinMode(segmentA, OUTPUT);
  pinMode(segmentB, OUTPUT);
  pinMode(segmentC, OUTPUT);
  pinMode(segmentD, OUTPUT);
  pinMode(segmentE, OUTPUT);
  pinMode(segmentF, OUTPUT);
  pinMode(segmentG, OUTPUT);
  pinMode(segmentDP, OUTPUT);
  
  // 初始化数码管
  digitalWrite(digit1, LOW);
  digitalWrite(digit2, LOW);
  digitalWrite(digit3, LOW);
  digitalWrite(digit4, LOW);
  digitalWrite(segmentA, HIGH);
  digitalWrite(segmentB, HIGH);
  digitalWrite(segmentC, HIGH);
  digitalWrite(segmentD, HIGH);
  digitalWrite(segmentE, HIGH);
  digitalWrite(segmentF, HIGH);
  digitalWrite(segmentG, HIGH);
  digitalWrite(segmentDP, HIGH);
}

void loop() {
  // 读取电流传感器的值
  int sensorValue = analogRead(currentSensorPin);
  // 通过电压读数计算电流值，电流传感器板卡的放大倍数是100
  current = sensorValue * 5.0 / 1023.0 / 0.05;
  
  // 更新数码管显示的值
  digit1_val = int(currentThreshold) / 10;
  digit2_val = int(currentThreshold) % 10;
  digit3_val = forwardTime / 1000 / 10;
  digit4_val = forwardTime / 1000 % 10;
  
  // 如果电流超过保护值，停止电机运行
  if (current > currentThreshold) {
    stopMotor();
  }
  
  // 判断电机状态，控制电机正反转和暂停
  switch (motorState) {
    case 0:  // 电机停止状态
      if (digitalRead(startButtonPin) == LOW) {  // 启动按键按下，开始启动电机
        startMotor();
      }
      break;
    case 1:  // 电机正转状态
      digitalWrite(motorPin1, HIGH);
      digitalWrite(motorPin2, LOW);
      currentTime = millis() - startTime;
      if (currentTime >= forwardTime) {  // 正转时间到达，进入暂停状态
        pauseMotor();
      }
      break;
    case 2:  // 电机反转状态
      digitalWrite(motorPin1, LOW);
      digitalWrite(motorPin2, HIGH);
      currentTime = millis() - startTime;
      if (currentTime >= backwardTime) {  // 反转时间到达，进入暂停状态
        pauseMotor();
      }
      break;
    case 3:  // 电机暂停状态
      digitalWrite(motorPin1, LOW);
      digitalWrite(motorPin2, LOW);
      currentTime = millis() - stopTime;
      if (currentTime >= pauseDuration) {  // 暂停时间到达，重新开始正转
        startMotor();
      }
      break;
  }
  
  // 更新数码管显示
  updateDisplay();
  
  // 稍微延迟一下，避免显示闪烁
  delay(10);
}

void startMotor() {
  motorState = 1;
  digitalWrite(motorPin1, HIGH);  // 先正转一下，避免电机卡死
  digitalWrite(motorPin2, LOW);
  delay(1000);
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, LOW);
  startTime = millis();
}

void stopMotor() {
  motorState = 0;
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, LOW);
  stopTime = millis();
}

void pauseMotor() {
  motorState = 3;
  digitalWrite(motorPin1, LOW);
  digitalWrite(motorPin2, LOW);
  stopTime = millis();
}

void updateDisplay() {
  // 数码管位选
  digitalWrite(digit1, LOW);
  digitalWrite(digit2, HIGH);
  digitalWrite(digit3, HIGH);
  digitalWrite(digit4, HIGH);
  // 数码管段选
  displayDigit(digit1_val);
  
  digitalWrite(digit1, HIGH);
  digitalWrite(digit2, LOW);
  digitalWrite(digit3, HIGH);
  digitalWrite(digit4, HIGH);
  displayDigit(digit2_val);
  
  digitalWrite(digit1, HIGH);
  digitalWrite(digit2, HIGH);
  digitalWrite(digit3, LOW);
  digitalWrite(digit4, HIGH);
  displayDigit(digit3_val);
  
  digitalWrite(digit1, HIGH);
  digitalWrite(digit2, HIGH);
  digitalWrite(digit3, HIGH);
  digitalWrite(digit4, LOW);
  displayDigit(digit4_val);
}

void displayDigit(int digit) {
  switch (digit) {
    case 0:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, LOW);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, HIGH);
      digitalWrite(segmentDP, HIGH);
      break;
    case 1:
      digitalWrite(segmentA, HIGH);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, HIGH);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, HIGH);
      digitalWrite(segmentG, HIGH);
      digitalWrite(segmentDP, HIGH);
      break;
    case 2:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, HIGH);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, LOW);
      digitalWrite(segmentF, HIGH);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 3:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, HIGH);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 4:
      digitalWrite(segmentA, HIGH);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, HIGH);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 5:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, HIGH);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 6:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, HIGH);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, LOW);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 7:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, HIGH);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, HIGH);
      digitalWrite(segmentG, HIGH);
      digitalWrite(segmentDP, HIGH);
      break;
    case 8:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, LOW);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
    case 9:
      digitalWrite(segmentA, LOW);
      digitalWrite(segmentB, LOW);
      digitalWrite(segmentC, LOW);
      digitalWrite(segmentD, LOW);
      digitalWrite(segmentE, HIGH);
      digitalWrite(segmentF, LOW);
      digitalWrite(segmentG, LOW);
      digitalWrite(segmentDP, HIGH);
      break;
  }
}

需要使用一个电流传感器来测量电机的电流值，并且需要自己实现一个数码管显示。在代码中，我使用了一个共阴数码管和12个数字引脚和4个位选引脚来实现显示。按键可以用一个带上拉电阻的普通按钮来实现。另外，需要注意电机正反转控制继电器的接法，以及电流传感器的放大倍数和偏置电压的设置。