> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/handbook/di-30-zhang-chuan-xing-tong-xin/30.1.-gai-shu.md).

# 30.1.概述

UNIX® 一直以来都支持串行通信，因为最早的 UNIX® 机器依赖串行线路做用户输入和输出。从平均每秒 10 个字符的串行打印机和键盘组成的终端时代起，事情发生了很大变化。本章介绍了在 FreeBSD 上使用串行通信的一些方式。

通过阅读本章，你将了解：

* 如何将终端连接到 FreeBSD 系统。
* 如何使用调制解调器拨号连接到远程主机。
* 如何让远程用户能使用调制解调器登录到 FreeBSD 系统。
* 如何通过串行控制台引导 FreeBSD 系统。

在阅读本章之前，你应该：

* 了解如何 [配置和安装定制内核](/handbook/di-10-zhang-pei-zhi-freebsd-nei-he/10.1.-gai-shu.md)。
* 理解 [FreeBSD 权限和进程](/handbook/di-3-zhang-freebsd-ji-chu/3.1.-gai-shu.md)。
* 能获取与 FreeBSD 一起使用的串行硬件的技术手册。


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