StarTech.com 6ft (1.8m) 1-Port USB to Serial RS232 Adapter, FTDI DB9 Serial DCE Adapter Cable, Null Modem, USB 2.0 - TAA

I bought one of these cables a couple years ago to talk to my Agilent 34401A precision meter and have been happily using it since. Recently I tried buying a less expensive one from another vendor and was sadly disappointed that while the cable was recognized by my computer, it failed to communicate with my meter. So, I just bought a second one of these, and it simply works. It's so lovely to have a thing just work... and this cable works.

Excellent! Brought new life to older test equipment that used serial only. Now it has a USB com serial port

Great because it uses FTDI chipset which is very important. Prolific chipsets are not as reliable. Plugged it in my Win10 PC and let Windows deal with it. Said it installed OK but I had to do a driver update in Control Panel Device Manager. I pointed it to the included driver disk's Win10 FTDI folder and it worked great. Next best thing is it has a built in null modem and the correct female DB9 connector so no having to use separate null modem or gender changer. The final plus are the LEDs. The green LED (transmitting to USB end of cable) blinks to let you know data is uploading from the device while an orange one blinks to indicate serial traffic coming to the device on the RS-232 DB9 end. This eliminates another bulky serial port tester and allows for instant visual feedback of serial port activity. Finally, the DB9 has twin thumb screws to secure it to the device to ensure it doesn't come off even if the device is handled. I personally use this to manage my vintage HP 48SX calculator inside an environmental case that has a RS-232 male connector on the outside.

Completely painless to get working under Linux, and works just as expected, operating at standard RS-232 levels (±5V; it is not a TTL serial port). The TX/RX activity LEDs are a great feature, and it supports up to 3000000 baud (3 Mbaud). I have a laptop with integrated serial ports, but this is kind of better, since it gives you visual activity indicators and has a higher maximum speed. If you need to work with older equipment that uses RS-232, this is a great option.

I have been very happy with these. I have used them under both linux and macos. They are very convenient for serial consoles and the like. The blinking LEDs are fun but not needed.I, in general, have been very pleased with the FTDI chipset that this uses. Recent action by FTDI has demonstrated though that they have a willingness to purposely destroy people equipment in their attempts to stop counterfeiting of their products. They pushed out a driver for windows that purposely rendered counterfeit FTDI chips. The wikipedia page on FTDI has details and links.I have no reason to suspect that startech doesn't use genuine FTDI chips. It is next to imposable though for me as an end user and without destroying such a product to know if a product using a FTDI driver won't suddenly stop working when it gets plugged into a windows box. With my luck this will happen at the worst time and when I don't have an extra, non-FTDI USB to serial adapter with me.The net result is that if something claims a FTDI you can't trust it to work when you need it. I was beginning to prefer FTDI's chips and products based on them. Now I cannot trust them.

On Windows 10 I just plugged it into the computer, which recognized the chip set and installed the driver. Then plugged the DB9 into my device, looked in the device manager to see what port was assigned, and set my device software accordingly. Five minutes max

Works well to connect to the serial console on my PC Engines APU2 router. Linux detected it as /dev/ttyUSB0 without resorting to the driver CD that StarTech ships in the box. sudo grep -i tty syslog. Teklager has a very good description of how to make this connection from Linux using PuTTY.

One of the nicest null modem cables I've used. Works flawlessly in Windows 10 off a USB 3 port. I love how it has lights on it so I can confirm rcx and trx signals. I've used this successful to log into a number of network appliance consoles. No drivers were needed in Windows 10, it was plug and play. It does come with a driver disk if you need it for older OSes.Due not that the DB9 side stick out a little bit further than normal because it has the electronics in it for the USB to Serial conversion, keep that in mind if you have to work in a tight space.