Overview of the Serial Communication Protocol
In Series

© Lead Image © 3355m, 123RF.com
We explore serial communications, from the electrical specs to protocols and libraries, with an example of serial communication with an Arduino.
The word "serial" in terms of computers might bring several things to mind. In modern times, it might be the universal serial bus (USB). Not too long ago, it might have brought to mind a 9-pin connector on the back of your desktop – or the even bigger 25-pin connector a bit before that. Different, still, the term might bring up memories of modems, printers, or peripherals connected to specialty computers. If you look at early mainframes, the serial port was the main interface to a text terminal and thus the human interface to the computer.
Some of these usages have been superseded by newer or different technologies, but serial is still alive and well. Although not as common on today's computer equipment, serial communication is far from gone, and its availability can provide some interesting possibilities for talking to unique hardware.
Basic Principles
In the simplest sense, an electric circuit used for communication just uses a completed circuit to represent a 1 and a broken circuit to represent a 0. See the "Telegraphy" sidebar for how this worked in real life for years. The limitation of a simple telegraphy circuit is that for each signal you want to send, you need a dedicated wire.
[...]
Buy Linux Magazine
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.

News
-
Linux Kernel 6.16 Released with Minor Fixes
The latest Linux kernel doesn't really include any big-ticket features, just a lot of lines of code.
-
EU Sovereign Tech Fund Gains Traction
OpenForum Europe recently released a report regarding a sovereign tech fund with backing from several significant entities.
-
FreeBSD Promises a Full Desktop Installer
FreeBSD has lacked an option to include a full desktop environment during installation.
-
Linux Hits an Important Milestone
If you pay attention to the news in the Linux-sphere, you've probably heard that the open source operating system recently crashed through a ceiling no one thought possible.
-
Plasma Bigscreen Returns
A developer discovered that the Plasma Bigscreen feature had been sitting untouched, so he decided to do something about it.
-
CachyOS Now Lets Users Choose Their Shell
Imagine getting the opportunity to select which shell you want during the installation of your favorite Linux distribution. That's now a thing.
-
Wayland 1.24 Released with Fixes and New Features
Wayland continues to move forward, while X11 slowly vanishes into the shadows, and the latest release includes plenty of improvements.
-
Bugs Found in sudo
Two critical flaws allow users to gain access to root privileges.
-
Fedora Continues 32-Bit Support
In a move that should come as a relief to some portions of the Linux community, Fedora will continue supporting 32-bit architecture.
-
Linux Kernel 6.17 Drops bcachefs
After a clash over some late fixes and disagreements between bcachefs's lead developer and Linus Torvalds, bachefs is out.