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Chapter 14, How to Build a Wearable Computer
WARNING
As you connect the components together, be very careful to cover exposed
power supply cables and connectors. If these are accidentally shorted together,
the power supply and/or battery may heat up and cause a fire.
Your keyboard and pointer input devices will likely interface to the main
computer via a serial, PS/2, or USB connection.
Your head-mount display will connect to a video output card or port.
Depending on which display you have chosen, your output signal will be
either VGA or NTSC. If it is NTSC, the display device will probably require
a standard NTSC video output from the main CPU board. If your system
has only a VGA port, you can purchase a VGA-to-NTSC converter from
various sources (do a search for “VGA-to-NTSC converter” on the Web).
You can also use the TVator product introduced in Chapter 7.
Software Setup Instructions
Depending on your goals, the software can be the most challenging part
of this project. Standard operating systems assume that you have a large,
high-resolution display and a large power source. Wearable systems often
do not have particularly high-resolution displays and operate off of limited
battery displays. Many times the display cannot easily be used, and other
forms of human interface must be used instead.
You should first decide what you want your wearable system to do. It may
simply be built for the fun of building it, or you may want to solve a par-
ticular problem. You will also have to consider which operating system will
support the hardware you have on hand.
Operating system software
Several popular operating systems can be used on wearable computers,
including Linux, Windows, Windows CE, QNX, Mac OS X, and others.
Due to the large number of operating systems available, I will limit my dis-
cussion to the most popular three as well as QNX, a small, free OS.
Your OS choice will depend on what you want your wearable system to
do. If you want to edit MS Word, Excel, and PowerPoint documents, you
should probably use Windows. If you want to experiment with smaller
memory footprint systems and are willing to play with the software a bit,
Linux might be the better choice.
Linux
Since Linux is an open source licensed software package, it is easy to
modify and operate on many CPU platforms. A number of interest groups
Software Setup Instructions
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