解决用vscode开发arduino时Serial未定义

在工作目录编辑c_cpp_properties.json文件
添加defines字段

{
    "configurations": [
        {
            "name": "Win32",
            "includePath": [
                "D:\\Program Files (x86)\\Arduino\\tools\\**",
                "D:\\Program Files (x86)\\Arduino\\hardware\\arduino\\avr\\**",
                "D:\\Program Files (x86)\\Arduino\\hardware\\tools\\avr\\avr\\include",
                "D:\\Program Files (x86)\\Arduino\\hardware\\tools\\avr\\lib\\gcc\\avr\\7.3.0\\include",
                "D:\\Program Files (x86)\\Arduino\\hardware\\arduino\\avr\\cores\\arduino"
            ],
            "forcedInclude": [
                "D:\\Program Files (x86)\\Arduino\\hardware\\arduino\\avr\\cores\\arduino\\Arduino.h"
            ],
            "intelliSenseMode": "msvc-x64",
            "defines": [
                "USBCON"
            ]
        }
    ],
    "version": 4
}