SparkFun Forums

[sport100]

I have just received a serial accelerometer from sparkfun and I am trying to understand how it works.

I have the serial connection connected to a serial gender changer, and the gender changer connected to a cable which goes into the DB25 serial port on my computer.

I have never worked with Hyperterminal before so I am not sure if I am using it correctly.

After I open a new connection, the "Connect To" screen opens and my only choices are "sofware modem", com3, and, tcp/ip. I always choose com3 but I can never get a response from the accelerometer.

I have two serial ports on my computer. How can I tell which port is Com1, Com2, or Com3? Will the accelerometer work with the setup I am using through the DB25 pin serial port? If I used a serial to USB connector, would this solve my problems?

Thank you in advance.

[Kuroi Kenjin]

25-pin DB!?! How old is this computer? And which windows is it running? I haven't seen a computer with a 25-pin DB since I was too young to remember (I think they went out in the late 80's??). Also, are you on a laptop?

A USB-Serial Converter would add another serial port to your computer. I dunno if that would solve the problem, but would side step it. That's odd the COM1 and COM2 aren't showing up. Check you device manager (Under XP, in system, hardware tab... check the ports).

[Philba]

first off, verify which port you are using. on the non-PC end of the cable, jumper pin2 to pin3. then in hyperterminal, everything you type should be echoed. if not, you have opend the wrong port.

[daemondust]

Are you sure you haven't connected to a parallel printer port?

[riden]

Following up on daemondust's comment, is the DB25 on the PC end male? If it is female, it is the parallel port. What Windows OS are you using? If it is XP, go to the Control Panel, System applet, and open the Device Manager and look at the Ports that XP thinks it has.

[sport100]

Following up on daemondust's comment, is the DB25 on the PC end male? If it is female, it is the parallel port. What Windows OS are you using? If it is XP, go to the Control Panel, System applet, and open the Device Manager and look at the Ports that XP thinks it has.

After reading the Toshiba user manual, it is a parallel port and the only port that the device manager is showing is labeled LPT1.

My computer is a Toshiba laptop that is three years old and is running XP.

I will go get a serial to usb converter today. Will that create another port in the device manager? What should I expect?

THanks again for all the help everybody

[transcendentnb2]

Yes, it'll create a new serial port in the device manager. It'll be a little different than normal serial ports and have different options, but as far as hyperterminal is concerned, it's just a regular ol' serial port.

Note, however, that if you wish to write any programs on your PC to use the serial port, you'll have to use the windows or some other API for the interface and not any direct access to the registers (even though direct access to the registers in XP or any NT based windows requires a special dll or such for normal serial ports).

[Kuroi Kenjin]

For writing a program to use the serial port, I highly recommend using with VB.net 2005 or C# 2005. The Express Editions are free from Microsoft. The Serial Port class takes 2 mins to learn, it's simple, and does simple as well as event driven communication. Best of all, it actually works (I've tried several other confusing, half-working third party APIs and even tried making my own.... not fun).