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hardware is integrated directly on the chip with the rest of the computer hardware. We
can find special-purpose processors among the following supplier groups:
Application-specific integrated circuits (ASIC) vendors If we cannot find the
specific special-purpose computer we desire, we can make one! Massive amounts
of development dollars are required, so our robot application would have to have
a really high sales volume to even consider this. Advanced Risc Machine (ARM)
computer cores can be paired with special-purpose circuitry and put on individ-
ual ASICs.
Fabless semiconductor companies Many very small computer companies
build special-purpose computers. Usually, they go to ASIC vendors to make their
designs into chips, but they have done the work and spread out the costs among
many customers. Find them in electronic design magazines and at conventions.
Consider searching for them on the Internet using the special-purpose function as
one of the keywords.

Many special-purpose functions have been integrated into computer circuits and
brought to market. The following special functions are available from several suppliers:

Wireless communications Chips exist that can convert and convey radio fre-
quency (RF) data signals directly into the computer circuit. These chips are used
in pagers, phones, radios, global positioning systems (GPSs), RF identification
tags, smart cards, and so on. If the robot application requires special-purpose com-
puters with similar capabilities, consider looking at the suppliers in these markets.
Be aware, however, that few of these chips are available in small quantities. They
are also difficult to apply.
Internet communications Many computer chips are available with integrated
local area network (LAN) interfaces that are used to connect to the Internet.
Further, some of these computers have integral software stacks that can process
the flow of Internet data in real time inside the chip. This sort of processing can
greatly speed up a robot if its design requires a great deal of information flow over
the Internet Protocol (IP).
Digital signal processing (DSP) DSP circuitry (to be defined shortly) is used
to process information in ways most general-purpose processors cannot. Study the
following DSP section. If a DSP is needed, consider
Texas Instruments’ OMAP DSP processor at www.TI.com
Analog Devices at www.analog.com
Analog controllers Many special-purpose processors have analog circuitry
right on the digital chip. One buzzword for this type of circuitry is mixed signal.
Such a technology has several advantages, but the leading one is cost. If the chip