树莓派4无法boot的解决步骤与方法

我已经等了几个星期才等到新订购的Raspberry Pi 4交付。我还为此特意预订了一个铝制外壳，让它看起来更酷。但是当我发现似乎无论怎样都无法boot新的树莓派时，失望之情可想而知。

当我打开电源时，红色LED指示灯亮起表示供电，风扇也可以工作。但绿色LED只闪了一下，然后根本没有响应。没有vedio输出，甚至我连接的键盘和鼠标上的LED也都没有亮。

有几个步骤可以解决这个问题。首先，我检查了官方网站，他们宣布由于EEPROM损坏，一些新的pi 4可能无法启动，并提供了以下解决方案来恢复EEPROM。

1.尝试恢复EEPROM

如果您的Raspberry Pi 4无法启动，则SPI EEPROM可能已损坏。

要检查，请取出SD卡，断开设备电源，然后重新连接。如果绿色LED不闪烁，则需要重新编程EEPROM：
下载引导程序将其解压缩到空的FAT格式SD卡并将其插入Raspberry Pi 4连接电源并等待绿色LED快速闪烁。
断开设备电源，将SD卡更换为已启动的设备，然后重新连接设备以查看设备是否正常工作。

2.升级您的Raspbian镜像

如果第一步没有解决您的问题，也许您的Raspbian镜像已过期并且不支持Raspberry Pi 4.您需要：

从官方网站下载最新镜像。建议使用官方Raspbian以确保您的Pi4正常工作。
解压镜像文件并将其写入SD卡。在OSX或Linux下你可以使用dd命令，在windows下你可能会发现rufus是一个有用的工具。
要启用SSH 功能，可以添加名为“SSH”的文件（不带后缀，如.txt）。这样可以在不连接外设的情况下实现Pi SSH功能。如果仍然没有响应。尝试下一步。

3.移除任何不必要的外围设备

由于Raspberry Pi 4比其前代产品具有更高的功率，如果您的电源适配器无法提供更多电流，它也可能导致启动失败。

在这种情况下，您可能需要拔掉所有不需要的外围设备，如显示器，键盘和鼠标，只留下电源和以太网连接。您需要另一台计算机以及yoru LAN路由器的登录优先级来搜索Pi的IP地址。

在OSX或Linux下，您可以在终端尝试ssh。在Windows下，您可能需要启用WSL 或使用像putty这样的ssh工具。如果您可以在本地网络上找到Pi 4并使用用户名“pi”和默认密码“raspberry”连接它。这意味着Pi4可以工作，您需要检查电源适配器和hdmi适配器。

Raspberry Pi 4 cannot boot? try following steps

I have been waited for weeks until the newly ordered Raspberry Pi 4 was delivered. I also ordered an aluminum case to make it looks cooler. It's not hard to imagine how disapointted when I found there seemed no way to boot the new toy.

When I switched on the power, the red LED lights to indicate power is supplied, the fan also works. But the green LED only flashed for a while and then no response at all. No vedio output, even the leds on my connected keyboard and mouse did not light at all.

There are several steps to solve the problem. First I checked the offical website, where they announced that because of EEPROM corruption, some new raspberry pi 4 may not be able to boot, and gave the following solution to recover the EEPROM.

1. Try to recover the EEPROM

If your Raspberry Pi 4 will not boot, it is possible that the SPI EEPROM has become corrupted. To check, remove the SD card, disconnect the device from power, then reconnect it. If the green LED does not flash, you will need to reprogram the EEPROM:

Download the bootloader Extract it to an empty FAT-formatted SD card and insert it into your Raspberry Pi 4 Connect the power and wait for the green LED to flash quickly.
Disconnect the device from power, replace the SD card with your booted one, connect the device back to see if it works.

2. Upgrade your Raspbian image

If the first step didnot solve yor problem, perhaps your Raspbian image is out of date and do not support Raspberry Pi 4. You need to:

Download the latest image from Official Website.It is recommanded to use the official Raspbian so as to make sure your Pi4 works.
Unzip the image file and write it into your SD card. under OSX or Linux you can use dd order, under windows you may find rufus is a usefull tool.
To enable SSH function, you can add a file with name "SSH" (with no suffix like .txt). This will enable the Pi SSH function headlessly.
If there is still no response. Try next step.

3. Remove any unecessary Peripheral

As Raspberry Pi 4 cosumes more power than its predecessors, if your power adapter cannot supply more current, it may also cause boot failure.

In this case you may need to remove all unecessay peripheral like monitor, keyboard and mouse, and only leave power supply and ethernet connection.
You need another computer as well as the login previlige of yoru LAN router to search for Pi's IP address.
under OSX or Linux you can try ssh in terminal. under windows you may need to enable WSL or use ssh tools like putty.
If you can find Pi 4 on your local network and connect it with user name "pi" and default password "raspberry". It means that Pi4 works, and you need to check your power adapter and hdmi adapter.