arduino LCD1602a什么问题显示不出数据

问题遇到的现象和发生背景

用代码块功能插入代码，请勿粘贴截图

不清楚什么原因，按网上打得
编译器：
AVRIDP mkll

原编码：

#include //声明调用库
 
const int rs=12,en=11,d4=5,d5=4,d6=3,d7=2;//对应引脚
LiquidCrystal lcd(rs,en,d4,d5,d6,d7);//创建一个名为lcd的实例（对象），这里是4线法d4~d7
void setup() {
  lcd.begin(16,2);//初始化LCD的宽度和高度,设置16列2行
  lcd.print("Hi,Emma!");//向LCD输出内容
}
 
void loop() {
  lcd.setCursor(0,1);//把光标设置在0列1行(第2行开头)上
  lcd.print(millis()/1000);//把系统运行的时间打到屏幕上
}

运行结果及报错内容

项目使用 1890 字节（5%）的程序存储空间。最大值为 32256 字节。
个全局变量使用 55 个字节（2%）的动态内存，剩下 1993 个字节用于局部变量。最大值为 2048 字节。

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 1 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 2 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 3 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 4 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 5 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 6 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 7 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 8 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 9 of 10: not in sync: resp=0x63
avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_getsync() attempt 10 of 10: not in sync: resp=0x63
上传失败: 上传错误：exit status 1

我的解答思路和尝试过的方法