MATLAB DESIGN HDL CODER RELEASE NOTES Uživatelská příručka Strana 24

  • Stažení
  • Přidat do mých příruček
  • Tisk
  • Strana
    / 410
  • Tabulka s obsahem
  • ŘEŠENÍ PROBLÉMŮ
  • KNIHY
  • Hodnocené. / 5. Na základě hodnocení zákazníků
Zobrazit stránku 23
24 www.xilinx.com System Generator for DSP User Guide
UG640 (v 12.2) July 23, 2010
Chapter 1: Hardware Design Using System Generator
In the System Generator portion of a Simulink model, every signal must be sampled.
Sample times may be inherited using Simulink's propagation rules, or set explicitly in a
block customization dialog box. When there are feedback loops, System Generator is
sometimes unable to deduce sample periods and/or signal types, in which case the tool
issues an error message. Assert blocks must be inserted into loops to address this problem.
It is not necessary to add assert blocks at every point in a loop; usually it suffices to add an
assert block at one point to “break” the loop.
Note:
Simulink can display a model by shading blocks and signals that run at different rates with
different colors (Format > Sample Time Colors in the Simulink pulldown menus). This is often useful
in understanding multirate designs
Bit-True and Cycle-True Modeling
Simulations in System Generator are bit-true and cycle-true. To say a simulation is bit-true
means that at the boundaries (i.e., interfaces between System Generator blocks and non-
System Generator blocks), a value produced in simulation is bit-for-bit identical to the
corresponding value produced in hardware. To say a simulation is cycle-true means that at
the boundaries, corresponding values are produced at corresponding times. The
boundaries of the design are the points at which System Generator gateway blocks exist.
When a design is translated into hardware, Gateway In (respectively, Gateway Out) blocks
become top-level input (resp., output) ports.
Timing and Clocking
Discrete Time Systems
Designs in System Generator are discrete time systems. In other words, the signals and the
blocks that produce them have associated sample rates. A block’s sample rate determines
how often the block is awoken (allowing its state to be updated). System Generator sets
most sample rates automatically. A few blocks, however, set sample rates explicitly or
implicitly.
Note:
For an in-depth explanation of Simulink discrete time systems and sample times, consult the
Using Simulink reference manual from the MathWorks, Inc.
A simple System Generator model illustrates the behavior of discrete time systems.
Consider the model shown below. It contains a gateway that is driven by a Simulink source
(Sine Wave), and a second gateway that drives a Simulink sink (Scope).
The Gateway In block is configured with a sample period of one second. The Gateway Out
block converts the Xilinx fixed-point signal back to a double (so it can analyzed in the
Zobrazit stránku 23
1 2 ... 19 20 21 22 23 24 25 26 27 28 29 ... 409 410

Komentáře k této Příručce

Žádné komentáře

Xerox DocuColor 250 manuals

Owner’s manuals and user’s guides for Printers Xerox DocuColor 250.
We providing 1 pdf manuals Xerox DocuColor 250 for download free by document types: User Manual






More products and manuals for Printers Xerox

Models Document Type
DocuColor 2060 NPS User Manual   Xerox DocuColor 2060 NPS User Manual, 38 pages
701P35371 User Manual   Xerox 701P35371 User Manual, 86 pages
DocuColor 5000AP User Manual   Xerox DocuColor 5000AP User Manual, 20 pages
CopyCentre/WorkCentre 118 MO3101Y6-1 User Manual   Xerox CopyCentre/WorkCentre 118 MO3101Y6-1 User Manual, 4 pages
DCC360 User Manual   Xerox DCC360 User Manual, 7 pages
3535 User Manual   Xerox 3535 User Manual, 268 pages
Phaser laser printer 4500 User Manual   Xerox Phaser laser printer 4500 User Manual, 10 pages
96/4635/180 IPS User Manual   Xerox 96/4635/180 IPS User Manual, 51 pages
3100MFP User Manual   Xerox 3100MFP User Manual, 12 pages
6360 User Manual   Xerox 6360 User Manual, 4 pages
SquareFold 610P729932 User Manual   Xerox SquareFold 610P729932 User Manual, 2 pages
Phaser 6180 User Manual   Xerox Phaser 6180 User Manual, 4 pages
DC98CC09 User Manual   Xerox DC98CC09 User Manual, 4 pages
XT3008EN0-2 User Manual   Xerox XT3008EN0-2 User Manual, 30 pages
2000 User Manual   Xerox 2000 User Manual, 2 pages
WorkCentre XD130DF User Manual   Xerox WorkCentre XD130DF User Manual, 1 pages
F12 User Manual   Xerox F12 User Manual, 4 pages
785 User Manual   Xerox 785 User Manual, 368 pages
DC220 User Manual   Xerox DC220 User Manual, 2 pages
8142 User Manual   Xerox 8142 User Manual, 1 pages