软件源

1.备份原文件

$ sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
$ sudo cp /etc/apt/sources.list.d/raspi.list /etc/apt/sources.list.d/raspi.list.bak

2.替换(buster版本)

$ sudo vi /etc/apt/sources.list
deb http://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/ buster main contrib non-free rpi
deb-src http://mirrors.tuna.tsinghua.edu.cn/raspbian/raspbian/ buster main contrib non-free rpi
$ sudo vi /etc/apt/sources.list.d/raspi.list
deb http://mirrors.tuna.tsinghua.edu.cn/raspberrypi/ buster main ui
deb-src http://mirrors.tuna.tsinghua.edu.cn/raspberrypi/ buster main ui

3.更新软件

$ sudo apt update && sudo apt-get update
$ sudo apt upgrade