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Spartan-3A DSP 3400A Edition User Guide
UG498 (v2.2) November 17, 2008
Preface:
About This Guide
R
Conventions
This document uses the following conventions. An example illustrates each convention.
Typographical
The following typographical conventions are used in this document:
Online Document
The following conventions are used in this document:
Convention
Meaning or Use
Example
Courier font
Messages, prompts, and
program files that the system
displays
speed grade: - 100
Courier bold
Literal commands that you enter
in a syntactical statement
ngdbuild
design_name
Italic font
References to other manuals
See the
Development System
Reference Guide
for more
information.
Emphasis in text
If a wire is drawn so that it
overlaps the pin of a symbol, the
two nets are
not
connected.
Square brackets [ ]
An optional entry or parameter.
However, in bus specifications,
such as
bus[7:0]
, they are
required.
ngdbuild
[
option_name
]
design_name
Braces { }
A list of items from which you
must choose one or more
lowpwr =
{
on
|
off
}
Vertical bar |
Separates items in a list of
choices
lowpwr =
{
on
|
off
}
Vertical ellipsis
.
.
.
Repetitive material that has
been omitted
IOB #1: Name = QOUT’
IOB #2: Name = CLKIN’
.
.
.
Horizontal ellipsis
. . .
Repetitive material that has
been omitted
allow block
block_name loc1
loc2 ... locn;
Convention
Meaning or Use
Example
Blue text
Cross-reference link to a location
in the current document
See the section
“Additional
Resources”
for details.
Refer to
“Title Formats” in
Chapter 1
for details.
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