Hardware Reference
In-Depth Information
this make counterfeiting euro notes virtually impossible, but it would make tracing
kidnapping ransoms, the loot taken from robberies, and laundered money much
easier to track and possibly remotely invalidate. When cash is no longer anony-
mous, standard police procedure in the future may be to check out where the sus-
pect's money has been recently. Who needs to implant chips in people when their
wallets are full of them? Again, when the public learns about what RFID chips can
do, there is likely to be some public discussion about the matter.
The technology used in RFID chips is developing rapidly. The smallest ones
are passive (not internally powered) and capable only of transmitting their unique
numbers when queried. However, larger ones are active, can contain a small bat-
tery and a primitive computer, and are capable of doing some calculations. Smart
cards used in financial transactions fall into this category.
RFID chips differ not only in being active or passive, but also in the range of
radio frequencies they respond to. Those operating at low frequencies have a limit-
ed data rate but can be sensed at great distances from the antenna. Those operating
at high frequencies have a higher data rate and a shorter range. The chips also dif-
fer in other ways and are being improved all the time. The Internet is full of infor-
mation about RFID chips, with
www.rfid.org
being one good starting point.
Next up the ladder we have computers that are embedded inside devices that
are not sold as computers. The embedded computers, sometimes called
microcon-
trollers
, manage the devices and handle the user interface. Microcontrollers are
found in a large variety of different devices, including the following. Some ex-
amples of each category are given in parentheses.
1. Appliances (clock radio, washer, dryer, microwave, burglar alarm).
2. Communications gear (cordless phone, cell phone, fax, pager).
3. Computer peripherals (printer, scanner, modem, CD ROM-drive).
4. Entertainment devices (VCR, DVD, stereo, MP3 player, set-top box).
5. Imaging devices (TV, digital camera, camcorder, lens, photocopier).
6. Medical devices (X-ray, MRI, heart monitor, digital thermometer).
7. Military weapon systems (cruise missile, ICBM, torpedo).
8. Shopping devices (vending machine, ATM, cash register).
9. Toys (talking doll, game console, radio-controlled car or boat).
A car can easily contain 50 microcontrollers, running subsystems including the
antilock brakes, fuel injection, radio, lights, and GPS. A jet plane can easily have
200 or more. A family might easily own several hundred computers without even
