This is the "famous" Keyspan: https://www.amazon.com/Tripp-Lite-Keyspan-High-Speed-USA-19HS/dp/B0000VYJRY/ It uses a Texas Instruments chipset and is very stable, and works like a champ. This is the less famous IOGear GUC232A: https://www.amazon.com/IOGEAR-Serial-RS-232-Adapter-GUC232A/dp/B000067VB7/ It uses a Prolific PL-2303HXC chipset, and is roughly half the cost of the Keyspan. The Prolific chipset devices tend to change COM ports when they feel like it and have a somewhat negative reputation largely caused by low-quality counterfit devices. I've been using one of these IOGear units for years. Someday when it dies, or if I need to move to USB-C, I'll probably upgrade to the Keyspan (which is available in a USB-C version). It doesn't really matter, so long as you buy an authentic product that is well manufactured. Answer from VA_Network_Nerd on reddit.com
Amazon
amazon.com › RS232-USB › s
Amazon.com: RS232 To USB
Browse a wide range of RS232 USB converters. Find the right adapter for your industrial or legacy equipment needs.
StarTech.com
startech.com › home › add-on cards & peripherals › serial cards & adapters › icusb232pro
1 ft USB to Serial DB9 Adapter Cable | USB Serial Adapters
1 ft USB to RS232 Serial DB9 Adapter Cable with COM Retention - TAA
1 ft USB to RS232 Serial DB9 Adapter Cable with COM Retention - TAA
Price $37.91
What USB-RS232 adaptors do y’all use and would it make any difference?
This is the "famous" Keyspan: https://www.amazon.com/Tripp-Lite-Keyspan-High-Speed-USA-19HS/dp/B0000VYJRY/ It uses a Texas Instruments chipset and is very stable, and works like a champ. This is the less famous IOGear GUC232A: https://www.amazon.com/IOGEAR-Serial-RS-232-Adapter-GUC232A/dp/B000067VB7/ It uses a Prolific PL-2303HXC chipset, and is roughly half the cost of the Keyspan. The Prolific chipset devices tend to change COM ports when they feel like it and have a somewhat negative reputation largely caused by low-quality counterfit devices. I've been using one of these IOGear units for years. Someday when it dies, or if I need to move to USB-C, I'll probably upgrade to the Keyspan (which is available in a USB-C version). It doesn't really matter, so long as you buy an authentic product that is well manufactured. More on reddit.com
28
12
September 19, 2023RS232 problems using a USB to Serial adapter cable - will a MAX232 help - Electrical Engineering Stack Exchange
I am trying to use an old RS232 device (Brother enbroidery card writer PE-Design v2.0) that used to work on the old PCs through the PCI Serial cards, DB-9 connector. With these newer computers I am More on electronics.stackexchange.com
Which USB-RS232 adapter to get?
I’ve used various cables with FTDI chips pretty successfully. My last one was a cheap AliExpress/eBay cable, but I can’t find it anymore so can’t point you in the right direction. 🤷♂️ More on reddit.com
28
7
November 4, 2025How to choose USB-RS232 cable?
In willing to bet that since your robot requires something specific, it also has a recommended cable More on reddit.com
31
1
March 13, 2026How do I install my USB serial adapter in Windows XP? (.exe method)
Prior to installing this device, ensure that your operating system is up to date (for example, you have installed the most recent service pack). To install the driver: Download the latest drivers from the StarTech.com website ( http://www.startech.com/Support ). You can find the part number and product ID on the product’s packaging. Note: Windows will typically save the files to the Downloads folder that is associated with your user account (for example, C:\Documents and Settings\ your_name \My Documents\Downloads). Once the download is complete, right-click the zip folder that you downloaded,
startech.com
startech.com › home › add-on cards & peripherals › serial cards & adapters › icusb232pro
1 ft USB to Serial DB9 Adapter Cable | USB Serial Adapters
How do I confirm that Windows detects my USB device?
To confirm that Windows detects your USB device, complete the following: Press the Windows key+ R , type devmgmt.msc , and press Enter . In Device Manager , under the appropriate heading, confirm that your expansion card is listed and that there isn't an exclamation mark next to it. For example, a USB controller card would be under Universal Serial Bus controllers . Your USB device is listed according to the name of the chipset. To determine the name of the chipset of your USB device, navigate to www.StarTech.com and look on the Technical Specifications tab for your product.
startech.com
startech.com › home › add-on cards & peripherals › serial cards & adapters › icusb232pro
1 ft USB to Serial DB9 Adapter Cable | USB Serial Adapters
Serial communication is not working. Is the problem caused by the adapter or my serial software application?
Older applications that use serial communication often use legacy hardware addresses that do not work with PCI, PCIe, or USB to Serial products. We recommend contacting the software provider/support team to check if this is the case.
startech.com
startech.com › home › add-on cards & peripherals › serial cards & adapters › icusb232pro
1 ft USB to Serial DB9 Adapter Cable | USB Serial Adapters
Videos
03:11
How to Make a USB to RS232 Serial Cable (Pick the Right Converter) ...
04:29
How to Wire RS232 Connections - YouTube
01:59
USB to RS-232 DB9 Serial Adapter Cables | StarTech.com - YouTube
01:09
SABRENT USB 2.0 to Serial (9-Pin) DB-9 RS-232 Converter Cable, ...
03:44
DriverGenius SerialPulseX Series USB-C to RS-232 Converter w/ 9-LED ...
02:00
USB to Serial Adapter Cable with COM Retention | StarTech.com - ...
CommFront
commfront.com › products › usb-to-single-rs232-adapter-converter
USB to RS232 Adapter / Converter – CommFront
SG12/04213, strictly certified by SGS), and we back our high-quality products with a 5-year replacement warranty and a 30-day risk-free money-back guarantee. USB to RS232 adapter / converter.
StarTech.com
startech.com › home › usb serial adapters
USB Serial Adapters - RS232 | DB9 | RJ45 | StarTech.com
Our USB to RS-232 Serial Adapters offer a reliable and cost-effective way to bridge legacy serial devices with USB-enabled systems that lack support for serial peripherals.
CDWG
cdwg.com › product › C2G-1.5ft-USB-to-DB9-Serial-RS232-Adapter-Cable-Blue › 297778
C2G 1.5ft USB to Serial Cable - USB to DB9 Serial RS232 Cable - M/M - 26886 - USB Adapters - CDWG.com
Note: Using this adapter with a Chromebook requires a serial terminal application. This type of application may be downloaded from the Chrome Web Store. ... C2G 1.5ft USB to DB9 Serial RS232 Adapter Cable is rated4.41 out of5 by95.
Reddit
reddit.com › r/cisco › what usb-rs232 adaptors do y’all use and would it make any difference?
r/Cisco on Reddit: What USB-RS232 adaptors do y’all use and would it make any difference?
September 19, 2023 - The famous keyspan used an achor chips ez-usb chip (later bought by cypress, fx2 and fx3 are the same lineage). ... I use an FTDI type and it has worked well for me for years now. ... RJ45 port on the other end so i don't have to pack around an adaptor. Never had any issues. ... I've been using those lately too and have had good luck with them. Finally dumped a good portion of my serial cable box and bought a handfull of these because I was tired of digging through it trying to find a non null-modem cable, whatever appropriate adapters, a working usb serial adapter, etc
US Converters
usconverters.com › usb-serial-rs232-adapters
USB to Serial Adapter | USB Serial RS232 Cable from U. S. Converters
On this page you will find our RS232 versions with one, two or four serial ports in one converter, which means that you can add up to four serial RS232 ports to one computer. ... This PRO version mini Serial to USB adapter is similar to our STD mini...
FTDI
ftdichip.com › home › products › products › cables › usb rs232 cable series
USB RS232 Cable Series - FTDI
Return to shop · Home · / Products · / Cables · / USB RS232 Cable Series · Home · Products · IC · Modules · Cables · Applications · AUTOMOTIVE · ADAS · Car Diagnostics Device · EV Charger · Telematics Box · Vehicle Computer · Vehicle Radar ·
Coolgear
coolgear.com › home › industrial usb to serial adapters | rs232 rs422 rs485 | com port retention › usb to rs232
USB to RS232 - Coolgear
USB to RS232 Adapter – 2500Vrms Isolation Industrial 8-Port DB-9 RS232 to USB Adapter to add eight new or additional serial devices to your system.… ... USB to Serial Adapter – High Speed Prolific Chipset USB DB-9 Serial 72 inch RS-232 Adapter cable for connecting to serial devices without the need for…
USBGear
usbgear.com › usb-serial › usb-to-rs232.html
USB to RS232 - USB Serial
Add a 4 Port RS232 to USB adapter to your system without having to configure it! The USA-FTDI4x-NUT USB to Serial Adapter protects your devices from ESD and high voltage spikes and other electrical surges that may cause damage. Automatic handshaking 3ft. cable connection Compatible with serial ...
Sabrent
sabrent.com › collections › 10percent › usb 2.0 to serial db9 male (9 pin) rs232 cable adapter
USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter - Sabrent
USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter
· Provides the connection between USB and the traditional RS-232 serial port. · Supported OS: Windows 2000/ME/98SE, Windows XP (32/64-bit), Windows Vista (32/64-bit), Windows 7 (32/64-bit), Windows 8/8.1 (32/64-bit), Windows 10 and higher (32/64-bit), Mac OS X 10.6 and Above, Linux 2.4 or above. · Easy to setup: Plug & Play - Simply plug your device into the adapter and the adapter into your PC or Mac. · COM ports and Baud rates can be modified to desired set up. · This product comes with LIFETIME manufacturer warranty. ·
Price $11.99
Eaton
tripplite.eaton.com › products catalog › usb adapters › u209005com
RS232 to USB Adapter Cable, 5-ft | Eaton
It is backward compatible with USB 1.1 devices. COM Retention Feature for Convenient Reassigning of COM Values to Ports · The hot-swappable RS232-port-to-USB adapter with built-in FTDI chipset offers COM retention.
Waveshare
waveshare.com › wiki › USB-TO-RS232-Male-Cable
USB-TO-RS232-Male-Cable - Waveshare Wiki
Industrial USB to RS232 serial adapter cable, adopts original FT232RL chip, provides stable communication, an ideal choice for industrial control equipment and/or applications with high communication requirements.
L-com
l-com.com › home › usb 2.0 to rs232 converter cable, usb type a male to db9 male, pvc (polyvinyl chloride), 2-meter
USB 2.0 to RS232 Converter Cable, USB Type A Male to DB9 Male, PVC (Polyvinyl Chloride), 2-Meter
USB 2.0 to RS232 Converter Cable, USB Type A Male to DB9 Male, PVC (Polyvinyl Chloride), 2-Meter
Sabrent
sabrent.com › collections › 10percent › usb 2.0 to serial db9 male (9 pin) rs232 cable adapter 1 ft cable
USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter 1 ft Cable - Sabrent
USB 2.0 To Serial DB9 Male (9 Pin) RS232 Cable Adapter 1 ft Cable
· Single cable USB to serial communication · USB full speed communication and bus-powered · Supports automatic handshake mode · Supports the RS-232 serial interface (standard 9-pin serial) · 1-ft or 0.3m length ·
Price $29.99
Serialcomm
serialcomm.com › USB_adapters › USB_converters › usb_to_rs232_adapter › usb_to_rs232_adapter.product_general_info.aspx
USB to RS232 Adapter / USB to RS232 Converter
USB to RS232 Adapter / USB to RS232 Converter
USB to RS232 Converter with an FTDI driver - Mac/Win 11/10 Compatible - 5-year replacement warranty
Price $19.95
StarTech.com
startech.com › home › add-on cards & peripherals › serial cards & adapters › 1p6ffc-usb-serial
6.6ft (2m) USB to Serial Adapter Cable, COM Retention, Interchangeable Screws/Nuts, USB-A to DB9 RS2
6.6ft (2m) USB to Serial Adapter Cable, COM Retention, Interchangeable Screws/Nuts, USB-A to DB9 RS232, FTDI IC, ESD Protection, Windows/macOS/Linux
Add RS-232 serial communication support to USB-A enabled Data Terminal Equipment (DTE - e.g., desktop or laptop), using this 6.6-foot (2-meter) straight through USB to Serial Adapter Cable.
Serial Port Expansion
The USB Serial Adapter adds an RS-232 serial DB/DE-9 (male) connector to a desktop or laptop via a USB Type-A port. Secure the adapter to a serial device, using pre-installed and removable slotted D-Sub thumbscrews or install the included DB-9 Nuts for compatibility with other serial peripheral devices or cables.
LED Indicators
Data transmission and reception LED indicators on t
Price $48.16
Top answer 1 of 4
3
Most of RS232 to USB adapters are low quality and don't work for that reason. They also may not support semi-exotic features like oddball baudrates (those that aren't multiples of 2400bps) or hardware handshaking.
Here are some other things you can check as well:
The most classic RS232 problem is mixing up Tx and Rx. In which case you need a "null modem" type of RS232 cable/adapter. It is a device consisting of DE-9 male to DE-9 female (optionally with a cable between them) where Tx and Rx are flipped internally. Not to be confused with a gender changer, which only switches between DE-9 male/female without flipping the signals.
Continuity/resistance test with multimeter between RS232 DE-9 pin 5 and USB-A connector pin 4. This is signal ground and must be present. (Pin-outs of these are easily found on the Internet)
Are there any hardware handshaking signals used by the device? If so these might not get passed on over the USB adapter. Most common are RTS and CTS on pin 8 and 9.
COM port settings: baudrate, stop bits, parity.
If none of that helps, it is oscilloscope troubleshooting time from there on.
2 of 4
2
You may need to go into the Windows Settings and assign a COM Port number between COM1 and COM4 for the USB adaptor to be recognised by old software.
Also it could be the case that the Brother software is attempting to manipulate the hardware of a UART directly in the PC, so it will not work unless you find a motherboard with hardware UART connections - some industrial PCs come with all 4 COM ports for instance .
Raspberry Pi Forums
forums.raspberrypi.com › board index › hardware and peripherals › interfacing (dsi, csi, i2c, etc.)
RS232 to USB serial communication - Raspberry Pi Forums
Hi, I might be not much help, but I can give you a list of usb-serial bridges chips/chip manufacturers that are tested (and are from long time on market) and should work fine with linux (starting from the best ): 1st FTDI - FT232/ FT230/231/234 - FTDI produces probably the best usb-serial bridges with very good drivers, 2nd/3rd Proliftic PL2303(or similar) - pretty good chips, now drivers work fine too - those ca be easier to found in USB - RS232 cables 2nd/3rd Silicon Labs CP2102(or similar) - I have good opinion on those and never had any serious troubles with them too Those HL-340/240/etc a
Quora
quora.com › Is-it-possible-to-carry-RS232-signals-over-a-USB-cable-1
Is it possible to carry RS232 signals over a USB cable? - Quora
Answer (1 of 5): > Is it possible to carry RS232 signals over a USB cable? I doubt the question means literally what it says, as ordinary USB cables clearly have USB connectors at each end and these won’t plug into RS232 ports. You could chop the connectors off and attach standard serial ...