Editing Serial port (section)

==Common applications for serial ports==
This list includes some of the more common devices that are connected to the serial port on a PC. Some of these such as modems and serial mice are falling into disuse while others are readily available. Serial ports are very common on most types of [[microcontroller]], where they can be used to communicate with a PC or other serial devices.

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* Dial-up [[modem]]s
* Configuration and management of [[Computer network|networking]] equipment such as [[Router (computing)|routers]], [[Network switch|switches]], [[Firewall (computing)|firewalls]], [[load balancer]]s
* [[GPS]] receivers (typically [[NMEA 0183]] at {{nowrap|4,800 bit/s}})
* [[Bar code scanner]]s and other [[point of sale]] devices
* [[LED]] and [[LCD]] text displays
* [[Satellite phone]]s, low-speed satellite modems and other satellite-based transceiver devices
* [[Flat-panel display]]s to control screen functions by external computer, other AV components or remotes
* Test and measuring equipment such as digital [[multimeter]]s and weighing systems
* Updating [[firmware]] on various consumer devices
* [[CNC controller]]s
* [[Uninterruptible power supply]] management and status reporting
* Stenography or [[Stenotype]] machines
* Software debuggers that run on a second computer
* Console or debugger interface to [[Microprocessor development board|microprocessor development or evaluation board]]s
* Industrial field buses
* [[Printer (computing)|Printer]]s
* [[Computer terminal]], [[teletype]]
* [[Computer network|Networking]] (Macintosh [[AppleTalk]] using RS-422 at {{nowrap|230.4 kbit/s}})
* Serial mouse
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Since the control signals for a serial port can be driven by any [[digital signal]], some applications used the control lines of a serial port to monitor external devices, without exchanging serial data. A common commercial application of this principle was for some models of [[uninterruptible power supply]] which used the control lines to signal loss of power, low battery, and other status information. At least some [[Morse code]] training software used a code key connected to the serial port to simulate actual code use; the status bits of the serial port could be sampled very rapidly and at predictable times, making it possible for the software to decipher Morse code. 

Serial computer mice may draw their operating power from the received data or control signals.<ref>{{cite web |last1=Chan |first1=Alvin |title=AN-681 PC Mouse Implementation Using COP800 |url=https://www.ti.com/lit/an/snaa005/snaa005.pdf |publisher=National Semiconductor |access-date=29 July 2023 |date=1990}}</ref><ref>{{cite web |title=AN519 Implementing a Simple Serial Mouse Controller |url=https://ww1.microchip.com/downloads/en/Appnotes/00519c.pdf |publisher=Microchip Technology Inc. |access-date=29 July 2023 |date=1997}}</ref>