In terms of signal integrity, you definitely want to have TxD / gnd on one pair and RxD / gnd on another. There are also established "standard" pinouts for doing this. EIA/TIA-561 for example. Note that these may or may not work well with the cable twists in an "Ethernet" cable. I've designed products using the (old) Cisco console cable pinout that's meant to work with a flat cable (not twisted). The pinout has symmetry so that (by crimping the cable flipped over) one can connect DCE to DTE. Note that the data signals are next to gnd in the cable and this wouldn't have a problem over your distances. If using twisted pairs, you would need to have one pair on pins 3,4 and another on pins 5,6. EDIT: this is similar in concept to the " YOST " pinout (which has DCD instead of DSR, and a flipped pinout). '561 Cisco 1 RI RTS 2 DCD DTR 3 DTR TxD 4 SG GND 5 RXD GND 6 TXD RxD 7 CTS DSR 8 RTS CTS Answer from Allan-H on reddit.com
Aggsoft
aggsoft.com › rs232-pinout-cable › serial-cable-connections.htm
Most Popular RS232 or Computer Serial Port Connectors
Discover the essential pinouts and signal details for common RS232 connectors including DB9, DB15, DB25, RJ45 for seamless serial cable connections.
Cable Tester
cable-tester.com › home › pin out › rs232 pin out
RS232 Pin Out | Connector Reference Guide
January 5, 2020 - Pin out diagram of a RS232 pin out with 9 pins d-sub connector (male & female). Also includes references guide to RS232 max cable length.
RS232 cable
In terms of signal integrity, you definitely want to have TxD / gnd on one pair and RxD / gnd on another. There are also established "standard" pinouts for doing this. EIA/TIA-561 for example. Note that these may or may not work well with the cable twists in an "Ethernet" cable. I've designed products using the (old) Cisco console cable pinout that's meant to work with a flat cable (not twisted). The pinout has symmetry so that (by crimping the cable flipped over) one can connect DCE to DTE. Note that the data signals are next to gnd in the cable and this wouldn't have a problem over your distances. If using twisted pairs, you would need to have one pair on pins 3,4 and another on pins 5,6. EDIT: this is similar in concept to the " YOST " pinout (which has DCD instead of DSR, and a flipped pinout). '561 Cisco 1 RI RTS 2 DCD DTR 3 DTR TxD 4 SG GND 5 RXD GND 6 TXD RxD 7 CTS DSR 8 RTS CTS More on reddit.com
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December 5, 2021RS232 and RS485 DB9 pinouts
Hi guys. In my current project i am trying to communicate with RS232 and RS485. Both should be present but one should be active. I am using MAX3160E transceiver, which allows me to switch between RS232 and RS485. Aim is to connect them to DB9 and control the transceiver to switch. But pin... More on forum.allaboutcircuits.com
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February 28, 2022RJ-12 to RS232 DB9
For the RJ12, it's Page 6-9 in the manual: https://cdn.automationdirect.com/static/manuals/p1userm/ch6.pdf The DB9 pinout should be standard. If it doesn't work, just switch the RX and TX on one end. More on reddit.com
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August 11, 2023RS-422 serial communication using CAT 6 RJ-45 Ethernet cable
Put down the serial connector and back away slowly. You're mixing protocols. More on reddit.com
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May 20, 2024What is the RS-232 9-pin pinout?
The RS-232 9-pin pinout refers to the specific signal assignment for each pin on a DB9 connector used in serial communication. Each of the 9 pins carries a distinct signal — including data transmission, handshaking, and ground — that allows two devices to communicate over a serial connection.
stratusengineering.com
stratusengineering.com › home › rs232 9 pin pinout: here’s what you need to know
RS232 9 Pin Pinout: Complete DB9 Pin Diagram & Wiring Guide
How do I monitor or capture RS-232 serial data?
To monitor RS-232 serial data without interrupting the connection, a passive tap device — such as the EZ-Tap or EZ-Tap Pro from Stratus Engineering — can be inserted inline between the DTE and DCE. This allows real-time data capture for debugging, logging, or protocol analysis.
stratusengineering.com
stratusengineering.com › home › rs232 9 pin pinout: here’s what you need to know
RS232 9 Pin Pinout: Complete DB9 Pin Diagram & Wiring Guide
What are the three most important pins on an RS-232 connector?
For basic serial communication, only three pins are required: Pin 2 (RXD – Received Data), Pin 3 (TXD – Transmit Data), and Pin 5 (GND – Signal Ground). All other pins support handshaking and flow control, which are optional depending on the application.
stratusengineering.com
stratusengineering.com › home › rs232 9 pin pinout: here’s what you need to know
RS232 9 Pin Pinout: Complete DB9 Pin Diagram & Wiring Guide
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Stratus Engineering
stratusengineering.com › home › rs232 9 pin pinout: here’s what you need to know
RS232 9 Pin Pinout: Complete DB9 Pin Diagram & Wiring Guide
July 20, 2016 - The complete RS232 9-pin pinout with labeled DB9 connector diagram, pin functions, and wiring details. Fast reference for engineers and technicians.
Just Add Power
support.justaddpower.com › kb › article › 488-serial-cable-pinouts
Serial Cable Pinouts - Just Add Power Support
July 31, 2023 - Serial cables are standardized to have 3 pins for communication: Send (TX) Receive (RX) Ground (GND) However, the position of those pins on each side of the cable may vary depending on the type of devices that are communicating · What is a Null Modem? Just Add Power RS232 Debug Cable · Null ...
PBXDom
pbxdom.com › blog › engineering › rs-232-cables-wiring-and-pinouts
RS-232 Cables, Wiring and PinoutsRS-232 Cables, Wiring and Pinouts - PBXDom
May 24, 2021 - RS-232 cables are a type of serial cable that uses the RS-232 standard. These cables have 25 pins. Unlike other types of data cabling, RS-232 is not used for video or audio signals.
Lammert Bies
lammertbies.nl › home › tutorials on computer interfacing › cables for data interfacing › rs232 serial cables pinout
RS232 serial cable pinout information - Lammert Bies
August 18, 2021 - The original pinout for RS232 was developed for a 25 pins sub D connector. Since the introduction of the smaller serial port on the IBM-AT, 9 pins RS232 connectors are commonly used.
RF Cafe
rfcafe.com › references › electrical › serial-port-pinout.htm
RS-232 Serial Port Pinout - RF Cafe
In telecommunications, RS-232 (Recommended Standard 232) is a standard for serial binary data signals connecting - Wikipedia
Virtual COM Port Driver
virtual-serial-port.org › virtual serial port driver › articles › what is serial port › rs232 pinout
All you have to learn about serial connector pinouts
October 3, 2024 - The plugs contain sockets and pins, with each pin numbered and labeled. A serial pinout diagram is presented below. The RS232 protocol uses a 9 pin serial port that can have either male or female connectors.
Shrubbery Networks
shrubbery.net › ~heas › rs232 › rs232.html
RS232 Cables, Wiring and Pinouts
A DB9 clearly has 9 connections and a cat5(e) cable has 8 conductors. RS232D has chosen to use Pin 1 as a multi-function pin (DSR/RI) to provide maximum flexibility with modems - in particular it allows for DCD which is a meaningful signal from a modem but not we suggest from a peer PC.
Reddit
reddit.com › r/askelectronics › rs232 cable
r/AskElectronics on Reddit: RS232 cable
December 5, 2021 -
If I were to use an RJ45 cable to transmit RS232 for 10 or 20 feet between RJ45 jacks, what would be the best practice for wiring? For example, use the blue and blue/white pair for RS232 TX (-11V) and GND, and use the orange and orange/white pair for RS232 RX (-11V) and GND. Ground all other wires?
Top answer 1 of 3
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In terms of signal integrity, you definitely want to have TxD / gnd on one pair and RxD / gnd on another. There are also established "standard" pinouts for doing this. EIA/TIA-561 for example. Note that these may or may not work well with the cable twists in an "Ethernet" cable. I've designed products using the (old) Cisco console cable pinout that's meant to work with a flat cable (not twisted). The pinout has symmetry so that (by crimping the cable flipped over) one can connect DCE to DTE. Note that the data signals are next to gnd in the cable and this wouldn't have a problem over your distances. If using twisted pairs, you would need to have one pair on pins 3,4 and another on pins 5,6. EDIT: this is similar in concept to the " YOST " pinout (which has DCD instead of DSR, and a flipped pinout). '561 Cisco 1 RI RTS 2 DCD DTR 3 DTR TxD 4 SG GND 5 RXD GND 6 TXD RxD 7 CTS DSR 8 RTS CTS
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Assuming you are not using hardware flow control then all you need to connect is TX, RX and ground. Other wires can be ignored.
US Converters
usconverters.com › index.php
RS232 Pinout : U.S. Converters LLC, Serial Data Communication
The primary purpose of the RS232 9-pin pinout is to establish connections between Data Terminal Equipment (DTE) and Data Communication Equipment (DCE), enabling effective data transmission between devices such as computers and modems. A null modem cable enables direct communication between ...
Extron
extron.com › download › files › userman › RS-232cablecard68-1353-01A.pdf pdf
9-pin D Male to Female RS-232 Cable Guide
The Extron RS-232 Cable interconnects RS-232 controlled devices within a professional A/V system.
Pccompci
pccompci.com › rs232-cable-technology.html
RS232 connector pin assignment
PCCOM RS232 RS422 RS485 Multi-port Serial card,Serial-TCP/IP Communication Product
Docklight
docklight.de › manual › rs232connectorspinout.html
RS232 Connectors / Pinout
•25-pole SUB D25 (RS232-C). This is the original connector introduced for the RS232 standard. It provides a secondary communication channel. •8-pole RJ45 (different pinouts for Cisco/Yost wiring, EIA/TIA-561, and other manufacturer-specific pinouts).
Wikipedia
en.wikipedia.org › wiki › RS-232
RS-232 - Wikipedia
1 week ago - The standard recommends the D-subminiature 25-pin connector up to revision C, and makes it mandatory as of revision D. Most devices only implement a few of the twenty signals specified in the standard, so connectors and cables with fewer pins ...
Bodenzord
bodenzord.com › archives › 117
RS-232 PC Serial Port Pinout Conventions | Bodenzord
October 3, 2013 - I had just such a need recently and discovered that there are two industry standard pinout conventions in use, the AT/Everex and the DTK/Intel. If you want to know more about how I discovered this and the differences, then continue reading. I’m in the process of building a server with Ubuntu 12.04, and I needed a serial connector to communicate with an APC Smart-UPS RT 1500VA RM. Although this UPS is capable of USB communication, APC uses a RJ45 connector on the back of the unit, and I didn’t own one the correct cable.
Eltima
eltima.com › home › blog › rs232 pinout and specifications
RS232 Pinout and Specifications Guide
3 weeks ago - All the clock signals on serial cable pins 15, 17, and 24 of the COM port pinout are for synchronous communications only. The clock is extracted from the data stream by DSU or the modem or DSU extracts and sent to the DTE to provide a steady ...
Plugable
kb.plugable.com › serial-adapter › what-is-the-pinout-of-the-rs-232-connector
What is the pinout of the RS-232 connector? - Plugable Knowledge Base
1 month ago - The RS-232 connector on the PL2303-DB9 uses a standard DTE pinout. The pin numbering can be found inside the DB9 connector of the adapter to identify the
Aggsoft
aggsoft.com › rs232-pinout-cable › RS232.htm
RS232 Port (DB-25). Pinout and Signals
Explore the complete pinout, wiring, and signal details for the RS232 DB25 serial port. Get the essential information you need to check or build a cable.
All About Circuits
forum.allaboutcircuits.com › home › forums › hardware design › digital design
RS232 and RS485 DB9 pinouts | All About Circuits
February 28, 2022 - God the days of having to carry around a "universal" set of adapters, null modems et all, USB has its problems, but at least it sorted that part out This look like a good link https://www.virtual-serial-port.org/article/what-is-serial-port/rs232-pinout/ https://www.pccompci.com/rs232-cable-technology.html