Instructables
Picture of The serial port - software setup
If you are trying to control something in the real world using your computer, the serial port is perhaps the easiest means of communication. I shall walk you through the process of setting up a serial port and hyperterminal on a computer running windows XP.
 
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Step 1: Find your serial port

Picture of Find your serial port
In order to set it up, first you have to find it on your computer. Long long ago, almost all computers had two serial ports, called "COM1" and "COM2", one a with a nine pin and the other with a 25 pin connector.

Now times have changed and the serial port has vanished.

Don't give up hope, however. The USB to serial converter has arrived, and it can be used instead. It is usually a dongle which plugs into a USB port, with a nine pin male connecter at the other end.

On my desktop computer, the motherboard has two built in serial ports. The third seial port, here labelled COM4, belongs to the USB to serial adapter I have plugged in.

So, to find the serial port on your computer, scout around its back. If you find a nine pin male connector (two rows, five and four, pins sticking out inside a metal shell) it has a serial port built in.

Or get a USB to serial converter and plug it in.

Open up Device Manager. Right click on "My Computer" and select properties (at the bottom of the list that pops up). Click on the "Hardware" tab. Click on the "Device Manager" button and a something similiar to this picture should appear.

Click on the '+' sign on the left of the "Ports (COM & LPT) to expand it. The list of printer and Serial ports available will be shown. Make a note of those, you will need them in the steps that follow.
nastier4 years ago
That is the correct pinout if you are looking directly at the female and it is correct if you are looking at the back of the male, where the cable connect. If you are looking at the front of the male or the rear of the female it will confuse you.
papalevies4 years ago
Nice tutorial. May I also suggest "PuTTy" for those who don't have hyperterminal (Vista/Linux/Mac users).
papalevies4 years ago
Are you sure this is the pinout? Because mine only works if you short out the 3rd and 4th from the left of the top row.
Forget my last message, I worked out how to do it, set "Flow control" to "none".
Can somebody please help me, the other day i bought myself a MAX233CPP chip and a serial connector from maplin, I soldered up a 4 conductor cable to the Rx pin (pin2), the Tx pin (pin 3) and ground (pin 5) but when I try sending data to it to view on my oscilloscope, nothing works. I tried DOS and Hyperterminal but they don't work. Can somebody please help me get it to work.
Derin6 years ago
HELP!!!!!vista does not have hyperterminal!
ReCreate Derin5 years ago
Err...try windows Xp Try again on a windows XP PC
neelandan (author)  Derin6 years ago
http://hp.vector.co.jp/authors/VA002416/teraterm.html

You can try downoading the program from the link above.
ReCreate5 years ago
Oh man somethings not right here,It tells me "Another program is using the selected telephony service" "Try again after the other program finishes" Whats this? Please HELP!!!
ReCreate5 years ago
I cant find it is it supposed to be in the default windows programs? Like stuff that are there when you install it. Can i have the exe of hyperterminal because i cant find it
russ_hensel6 years ago
Actually the usb port is usually easier to work, it sets itself up. Except when it doesn't. Also worth mentioning is that some usb devices set themselves up as virtual serial ports ( and if you do not have a serial port this is how usb to rs232 converters work). Very useful, you might want to extend it to include the usb virtual rs232.
you mean FTDT232 chips?
Wow, nice macro pictures of that loopy part. Great job.
I think neelandan used a scanner as it says in his other instructables. Must admit though, very good pictures.
rimar20006 years ago
Very interesting instructable. Can you give us any examples of things can be done with this?
neelandan (author)  rimar20006 years ago
Sure - the hardware part is going to come up next as an instructable.
benjgvps6 years ago
The serial port is handy, I made a cable to transfer files from my PC to my PowerBook 150 through the serial port. I use this wonderful program called "Stargate" which I have set up an archive for the site. http://68kmacwin.googlepages.com/stargatefiletransferarchive
sideways6 years ago
Nicely done Instructable. I have an old 486 laptop w/o USB or a cd-rom, so I keep a small DOS partition on one desktop. I boot the desktop to DOS and run Intersvr/Interlink on a serial between the two to move files to the laptop. Hey it's a kludge but it works. Don't laugh at my 486 laptop! I use it for a bookreader and it was dirt cheap. That little trick of wiring the two pins together was great, never come across it before.