NCD Articles Home Copyright © 2008, National Control Devices LLC
By Ryan Sheldon
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Introduction to Bluetooth Communications

Bluetooth is an ideal wireless platform for communicating large amounts of data within a short range.  Bluetooth is great for applications where a computer is not too far away from a device, but you just don't want to bother with connecting wires.  It's found its home in all kinds of peripheral devices and now has found a new home in embedded control applications.  Bluetooth, as it pertains to the NCD product line, is the easiest of all wireless technologies to implement.  It is only easier than ZigBee because it has NO drivers (our ZigBee modems use a USB driver).  However, to be technically correct, the driver is already on your computer, as it is part of the Bluetooth protocol.  Like all NCD devices, once the drivers are installed, you are ready to talk to the device as though it were directly connected to the COM port of your computer.  So Bluetooth is just as easy to use as any other device.

ProMOTE Software

The ProMOTE Software now ELIMINATES THE NEED FOR PROGRAMMING!  Simply download and install the free software, configure the buttons to fit your needs and your ready to go.  With no drivers required for the Bluetooth Connection and no programming for the control, what could
be easier! 

For more information
visit our ProMOTE Page.

Pairing NCD Devices Over a Bluetooth Connection
NCD Bluetooth devices need to be paired with a Bluetooth connection on your computer.  This involves opening the Bluetooth control panel on your computer, pressing the "pairing" button on our controller, and finally, using the Bluetooth control panel to add the device to the Bluetooth network.  Once paired, the NCD part number will appear in your Bluetooth control panel, and a new COM port will be available for use on your computer.  A Blue LED on our controller will NOT light up until you begin communicating with the device.  To communicate to the device, all you have to do is open the new Bluetooth COM port at 115.2K baud and start sending commands.  The Blue LED on our controller will light as soon as the port is opened.
At the Mercy of the Bluetooth Drivers
For once, we get to escape driver responsibility.  Meaning if you ever have problems with the Bluetooth drivers, you can thank your Bluetooth software for the problems, rather than anything we have done.  For me, it seems a little odd to offer a device with a wireless interface and NO drivers to talk to it.  It's about as close to pure RS-232 as you can get without using the real thing...and did I mention speed?  Bluetooth is the fastest of all wireless technologies we have implemented.  And surprisingly easy to use.  But its not without its limitations.
Ideal Bluetooth User
If you are looking to control our products from a laptop or PDA, Bluetooth is about as easy at it comes.  But unlike other wireless technologies, the maximum communication distance is around 100 meters.  A far cry from ZigBee, which is capable of communications at 1 mile (when using the high-end ZigBee modules, which are comparatively priced).  Bluetooth is great for a PDA or laptop talking to a few devices, but it really isn't as network friendly as ZigBee.  Most operating systems only support COM ports 1 through 255.  Some of these COM ports will be taken by other Bluetooth services.  Once you run out of COM ports, Bluetooth is at its limit.  While ZigBee has Bluetooth beat in terms of networking capabilities, Bluetooth still remains just ever so slightly easier to implement, and requires less hardware.  I expect we will see lots of users with PDAs and Laptops, looking for an inexpensive and easy way to connect to our devices without having to buy a specialized piece of hardware to communicate to these devices.
Advantages of Bluetooth Communications Disadvantages of Bluetooth Communications
Your laptop or PDA can probably talk to it with no additional hardware. Not as Network friendly as ZigBee
VERY VERY VERY EASY TO USE.  Acts like a COM port on your PC, so write your software accordingly. Limited 100 Meter Range in Compared to ZigBee Devices in the Same Price Category, Which are Capable of 1 Mile
Low Cost Interface   
Fastest Wireless Communication Speed we have Seen.  
Overall, the Most Convenient Choice for Wireless Communication to NCD Devices  
If you have any questions about this article, please feel free to contact me at or call our office at (417) 646-5644.  Our business hours are 9:00AM to 4:00PM Central Standard Time.