RS232 Breakout Tester LED Monitor, DB9 Male to Female Breakout Module

This breakout tester is absolutely essential for anyone working with serial communication on a regular basis. The problem with serial communication is that it either works or it doesn't, and there is very little, if any, sign of that's wrong, and there could be any number of things wrong. I cannot count how many times I've wired up a connection between two devices and had it not work. Did I use a null modem cable? Or is the device wired so I should be using a straight through cable? Is the device sending data? Maybe the baud rate is set wrong. Is the COM port I'm plugged into the right one? Or worse... what if two or more of those things are wrong? I guess I'll have to haul out other cables, a logic probe and a power source to run it, maybe a meter, and some little tiny wires to stick into those DB9 connectors to probe the pinout... Gimme an hour and maybe I'll have it working, you say to yourself.... This one little simple gadget solves all of that. Do I need a null modem cable or a straight through, or is the cable really what I think it is? Flip two switches and place a couple jumpers to reverse the TX and RX lines, and find out, without hunting around for other cables or busting out a meter to figure out what kind of cable you have. Want to know if the host is sending data? Is the peripheral responding? Are the send and receive happening on the right lines? No problem, look at the LEDs on the front and I know, at a glance. If your communication is more complex and is using the other pins, there are LEDs to tell you those statuses too. Want to snoop the line? No problem, just grab an FTDI cable and some jumpers and you can spy on the communication using the jumper ports. Or, use a second one of these boxes and do the same. I cannot state enough how much time this saves and how useful it is. It's small enough to carry around in a toolbox, robust enough to get banged up a good bit over time, and requires no batteries or additional power sources, it's powered by the line itself. I only wish I had bought one of these years ago.

If you're trying to solder together an old RS232 cable and not sure your connections are right, this little pocket sized device will help you out. You can see most of the major signals such as TX, RX, CTS, RTS, DCD, DTR, etc. It's also possible to turn off the pin to pin connectivity and use jumper wires to re-route a connection to try and get your serial port working. The only downside is that no jumper wires are provided, but you can use some thin wire, paperclip or even bread bag ties to make the jump. Otherwise, handy little device to have on hand.

gets the job done, but LEDs end up being on the bottom when plugged into a laptop with DB port in standard orientation. This makes it hard to see the LEDs with laptop on desk. I bought this to troubleshoot cables and needed to see signals as seen by laptop port. One needs a straight-through extension adapter to be able to flip this device and see LEDs. I wish LEDs were mounted such that they could be seen when plugged straight in.

You might need the DB25->DB9 adapter. Welcome to the 80's ... 1980's

This device works great for observing and debugging RS-232 stuff. Some folks complain about the test points not accepting dupont cables, they're sized for resistor leads, some breadboard cables (with round pins) and non-stacking arduino headers will also plug into them for use with dupont connector if needed (non stacking means the standard headers you'd find on arduino UNO, not the ones with long pins used on shields). They used the round socket strips because they had the same height as the dip switches. Photo shows RS-232 reconfigured with 10ohm resistors as an Agilent crossover cable, which solved the problem I got it to solve. The case was too bulky to plug directly into the back of my Agilent 34401A, so I used a stack of gender changers to get clearance.

My application wasn't very sophisticated, but this did show me what was going on with the serial connection I was troubleshooting.

It works very well. Use 22AWG solid wire. 24AWG works as well, but I find it a little sloppy. 22AWG fits perfectly and snug. Some people complain about the upside down DB9s - I say: “So what?”. It’s a great little tool. The photo shows a typical null modem configuration.

Are the days of serial data interception over? Maybe not. My plan is to insert this between an older piece of gear that sports a DB9 serial port and a USB to serial port adaptor in order to reverse engineer a data stream to a vector graphics robotic renderer. We'll see if my plan will work or not. Even if it does not, I am old school enough to appreciate having one of these in my tools/widgets piece-parts.

This tester was little bit costly. But good quality and very useful for me to Test comport datas

Buena calidad

rs232 シグナルを見ることが多いので、ちょっと高いですが購入いたしました。通常DB9の場合はDB25から変換していましたが、本製品でDB9直に確認できるようになった。

Perfect

He usado este modelo en el trabajo y es muy práctico por eso lo compré para mi Muy recomendable para verificar señales RS232 antes de conectar a tus equipos