Special-purpose processors.

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Introduction Special-purpose processors. Embedded
systems. FPGAs.
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Course overview Syllabus Schedule Project Stu
dent info (collect)
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Goal quickly and efficiently produce
special-purpose processors / software for
specific applications Hardware basis in this
course FPGAs (PLAs)
CARRY IN
GLOBAL BUS
BUS
MEM OUT
FPGA (EX)
LOCAL BUS
RAM BLOCK
CARRY OUT
SINGLE FPGA CELL
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• DESIGNING AN FPGA-BASED CIRCUIT / PROCESSOR
• USE HIGH-LEVEL ABSTRACTION
• USE HARDWARE DESCRIPTION LANGUAGES
• USE AUTOMATED TOOLS TO PRODUCE LAYOUT
• MAY FINE-TUNE DESIGN DETAILS
• DESIGN APPLICATION-SPECIFIC PROCESSOR /
  SOFTWARE

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Final product embedded system Reference
http//en.wikipedia.org/wiki/Embedded_system
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• Embedded system implemented in FPGA
• Special-purpose computer designed to be IN
  device it controls
• user is provided with a processor with basic
  functionality
• processor can be programmed in software
• Additional features can be added using the FPGA
  resources to customize the design for a specific
  intended use
• Processor core may be hard (built-in as part of
  the chip) or soft (using some of available FPGA
  resources. Ex Altera Nios II processor)
• Processor may have optionse.g., number of
  registers, floating point units
• Specialized CAD tools allow addition of
  additional functionality
• Hardware / software codesign now becomes a
  possibility

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The basic codesign processas presented at
http//ls12-www.cs.uni-dortmund.de/niemann/codes
ign/codesign.html
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Good embedded system reference http//www.ece.cmu
.edu/koopman/iccd96/iccd96.htmlintroduction Much
of the following information is taken from this
site

• Typical embedded system properties
• human interface--may be as simple as a flashing
  light or as complicated as real-time robotic
  vision.
• diagnostic port may be used for diagnosing the
  system that is being controlled -- not just for
  diagnosing the computer.
• Special-purpose field programmable (FPGA),
  application specific (ASIC), or even non-digital
  hardware may be used to increase performance or
  safety.
• Software often has a fixed function, and is
  specific to the application.

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Examples
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Design issues System may need to be real-time /
reactive (does not mean fast necessarily) Usuall
y must be small and not weigh much Must be safe
and reliable Must meet budget constraints
(cost) May need to work in harsh environmental
conditions (e.g., in an automobile)
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System requirements Focus is on end-use
capability, not on CPU performance, memory size,
etc. System software must be safe and
reliable Power usage should be low, depending on
applications System typically controls a physical
systemsensors / actuators
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Embedded system lifecycle / requirements Compone
ntssame component may work in several different
systemsthis can lower cost Safety
certificationmust often meet rigorous
requirements Recertificationif system is
modified Logistics / repairaccessibility is
important Upgradesneed to be handled
efficiently Component availabilitymay be
long-term needs
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business model What are design / production
costs? What is the life-cycle? Are there
product families?
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Design culture Computer/ VLSIsimulate,simulate,
simulate Mechanical/sensorsbuild, build,
build Differing world views need to be reconciled