Sensor Nets

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Embedded System Design Laboratory
EE 459Lx is a Capstone design course. All
seniors in Electrical Engineering are required to
take a Capstone course as part of the BS
curriculum. A Capstone course is intended to
provide a major design experience that draws upon
topics learned in previous semesters. Its a
great course no homeworks, no quizzes, no
exams, no textbook.

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Embedded System Design Laboratory
The EE department has multiple Capstone courses
on different topics. In EE 459 we build a
moderately complex project based on an embedded
system. An embedded system is a special purpose
computer that is designed into larger device in
order to perform a small number of dedicated
tasks. This is in contrast to a general
purpose computer that is designed to be a
stand-alone product and is intended to be used
for a variety of tasks, most of which will be
determined by the end user.

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Embedded systems are everywhere

• These days most homes probably have several dozen
  embedded systems in them
• Thermostat Refrigerator Security system
• Sprinkler timer Alarm clocks Remote controls
• Washing machine Stereo Answering machine
• Microwave oven TV Cordless phones
• VCR/DVD/DVR Garage door opener Video games
• Modern cars are also filled with many embedded
  systems that control nearly all aspects of its
  operation.

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Microcontrollers

• Embedded system are based on a microcontroller.
  Microcontrollers (or ?C) are a single integrated
  circuit that contains much of the functionality
  of a general purpose computer.
• Microcontroller
• Application specific hardware
• Software
• Embedded system

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Microcontrollers

Several manufacturer compete in the market for
microcontrollers (Freescale, Microchip, Atmel,
etc.). Each manufacturer produces multiple
lines or families of microcontrollers at
different levels of performance, intended for
products that require more or less
intelligence. Within each family there may be
dozens of different models, each optimized for
different tasks (automotive applications, motor
control, LCD display control, sensing analog
inputs, USB interfaces, etc.)
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Microcontrollers

EE459 teams use a ?C from Freescale called the
MC68HC908JL16. The JL16 microcontroller is far
simpler than a typical personal
computer. JL16 PC Clock
speed 10MHz 3gHz Data size 8 bits 32 or 64
bits RAM 512 bytes 1gb Storage 16kb 500gb Cost
3.23 1,000
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Tasks for the Engineering Teams
Preliminary Design Determine the basic
engineering requirements of the product. How
can these be implemented? What are the
tradeoffs of doing one type of circuit versus
another? Investigate different types of input
and output devices. Develop multiple solutions
to share with marketing and design teams.
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Tasks for the Engineering Teams
Final Design Expand on the selected design to
a more complete circuit. Select components that
meet the project requirements and are compatible
with other components in the design. Everything
has to work together. Develop
software. Develop test procedures to be used
during debugging of both hardware and software.
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Tasks for the Engineering Teams
Construction Build the hardware components of
the project on a prototyping board. Test parts
of the circuit as being built to confirm they
work as predicted.
EE 459 lab in OHE 240
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The Works-Like Prototype

The projects are constructed on prototyping
boards that make for easy debugging and
modification. On the wiring side of the board
wires are run between pins to make the electrical
connections.
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Tasks for the Engineering Teams
System Integration Debug hardware and software
to make them work together. Test project to
confirm it is working as specified. Make
modifications to design as required based on
input from rest of product design team. Produce
documentation (schematic diagrams, block diagram,
circuit description, parts list, cost estimate,
etc.)
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With any luck, it might actually work!