Altera RAM Initializer User Manual

RAM Initializer (ALTMEM_INIT)

Megafunction User Guide

101 Innovation Drive
San Jose, CA 95134
www.altera.com

Software Version: 8.0
Document Version: 1.0
Document Date: May 2008

Copyright © 2008 Altera Corporation. All rights reserved. Altera, The Programmable Solutions Company, the stylized Altera logo, specific device des­ignations, and all other words and logos that are identified as trademarks and/or service marks are, unless noted otherwise, the trademarks and
service marks of Altera Corporation in the U.S. and other countries. All other product or service names are the property of their respective holders. Al­tera products are protected under numerous U.S. and foreign patents and pending applications, maskwork rights, and copyrights. Altera warrants
performance of its semiconductor products to current specifications in accordance with Altera's standard warranty, but reserves the right to make
changes to any products and services at any time without notice. Altera assumes no responsibility or liability arising out of the ap­plication or use of any information, product, or service described herein except as expressly agreed to in writing by Altera
Corporation. Altera customers are advised to obtain the latest version of device specifications before relying on any published in­formation and before placing orders for products or services.

UG-01034-1.0

ii Confidential—Internal Use Only Altera Corporation
RAM Initializer (ALTMEM_INIT) Megafunction User Guide May 2008

Contents

About this User Guide ............................................................................. v

Revision History ........................................................................................................................................ v

Referenced Documents ............................................................................................................................. v

How to Contact Altera .............................................................................................................................. v

Typographic Conventions ...................................................................................................................... vi

Chapter 1. About this Megafunction

Device Family Support ......................................................................................................................... 1–1

Introduction ............................................................................................................................................ 1–1

Features ................................................................................................................................................... 1–2

General Description ............................................................................................................................... 1–3

Chapter 2. Getting Started

Software and System Requirements ................................................................................................... 2–1

MegaWizard Plug-In Manager Customization ................................................................................. 2–1

MegaWizard Plug-In Manager Page Descriptions ........................................................................... 2–2

Instantiating Megafunctions in HDL Code or Schematic Designs ................................................. 2–8

Generating a Netlist for EDA Tool Use ......................................................................................... 2–8

Using the Port and Parameter Definitions .................................................................................... 2–9

Identifying a Megafunction after Compilation ................................................................................. 2–9

Simulation ............................................................................................................................................... 2–9

Quartus II Software Simulator ....................................................................................................... 2–9

EDA Simulator ................................................................................................................................ 2–10

Design Example 1: RAM Initialization with Initialization Data File ........................................... 2–10

Design Files ..................................................................................................................................... 2–10

Configuration Settings ................................................................................................................... 2–11

Functional Simulation in the ModelSim-Altera Simulator ...................................................... 2–11

Understanding the Simulation Results ....................................................................................... 2–12

Design Example 2: Memory Initialization with External ROM .................................................... 2–15

Design Files ..................................................................................................................................... 2–15

Configuration Settings ................................................................................................................... 2–16

Functional Simulation in the ModelSim-Altera Simulator ...................................................... 2–16

Understanding the Simulation Results ....................................................................................... 2–17

Conclusion ............................................................................................................................................ 2–19

Chapter 3. Specifications

Ports and Parameters ............................................................................................................................ 3–1

Altera Corporation iii

RAM Initializer (ALTMEM_INIT) Megafunction User Guide

Contents

iv Confidential—Internal Use Only Altera Corporation
RAM Initializer (ALTMEM_INIT) Megafunction User Guide

About this User Guide

Revision History

Date and Document

Version

May 2008
v1.0

Referenced Documents

How to Contact Altera

The following table shows the revision history for this user guide.

Changes Made Summary of Changes

Initial release. —

This user guide references the following documents:

■ Quartus II Integrated Synthesis chapter in volume 1 of the Quartus II

Handbook

■ Recommended HDL Coding Styles chapter in volume 1 of the Quartus II

Handbook

■ Simulation section in volume 3 of the Quartus II Handbook

■ Synthesis section in volume 1 of the Quartus II Handbook

For the most up-to-date information about Altera® products, refer to the
following table.

Contact (1)

Technical support Website www.altera.com/support

Technical training Website www.altera.com/training

Product literature Website www.altera.com/literature

Non-technical support (General)

(Software Licensing)

Note to table:

(1) You can also contact your local Altera sales office or sales representative.

Contact
Method

Email [e-mail]

Email [e-mail]

Email [e-mail]

Address

Altera Corporation Confidential—Internal Use Only v
May 2008 RAM Initializer (ALTMEM_INIT) Megafunction User Guide

Typographic Conventions

Typographic

This document uses the typographic conventions shown in the following
table.

Conventions

Visual Cue Meaning

Bold Type with Initial
Capital Letters

bold type External timing parameters, directory names, project names, disk drive names,

Italic Type with Initial Capital
Letters

Italic type Internal timing parameters and variables are shown in italic type.

Initial Capital Letters Keyboard keys and menu names are shown with initial capital letters. Examples:

“Subheading Title” References to sections within a document and titles of on-line help topics are

Courier type Signal and port names are shown in lowercase Courier type. Examples: data1,

1., 2., 3., and
a., b., c., etc.

● • Bullets are used in a list of items when the sequence of the items is not important.

■

v The checkmark indicates a procedure that consists of one step only.
1 The hand points to information that requires special attention.

c

w

r The angled arrow indicates you should press the Enter key.

f The feet direct you to more information about a particular topic.

Command names, dialog box titles, checkbox options, and dialog box options are
shown in bold, initial capital letters. Example: Save As dialog box.

filenames, filename extensions, and software utility names are shown in bold
type. Examples: \qdesigns directory, d: drive, chiptrip.gdf file.

Document titles are shown in italic type with initial capital letters.
Example: AN 75: High-Speed Board Design.

Examples: t

Variable names are enclosed in angle brackets (< >) and shown in italic type.
Example: <file name>, <project name>.pof file.

Delete key, the Options menu.

shown in quotation marks. Example: “Typographic Conventions.”

PIA

, n + 1.

tdi, input. Active-low signals are denoted by suffix n, e.g., resetn.

Anything that must be typed exactly as it appears is shown in Courier type. For
example:
actual file, such as a Report File, references to parts of files (e.g., the AHDL
keyword
Courier.

Numbered steps are used in a list of items when the sequence of the items is
important, such as the steps listed in a procedure.

A caution calls attention to a condition or possible situation that can damage or
destroy the product or the user’s work.

A warning calls attention to a condition or possible situation that can cause injury
to the user.

c:\qdesigns\tutorial\chiptrip.gdf. Also, sections of an

SUBDESIGN), as well as logic function names (e.g., TRI) are shown in

vi Confidential—Internal Use Only Altera Corporation
RAM Initializer (ALTMEM_INIT) Megafunction User Guide May 2008

Chapter 1. About this

Megafunction

Device Family Support

The RAM Initializer (ALTMEM_INIT) megafunction supports the
following target Altera

■ ACEX

■ APEX™ II

■ APEX 20KC

■ APEX 20KE

■ Arria™ GX

■ Cyclone

■ Cyclone II

■ Cyclone

■ FLEX 10K

■ FLEX

■ FLEX 10KE

■ FLEX 6000

■ HardCopy

■ HardCopy Stratix

■ MAX

■ MAX 3000A

■ MAX 7000AE

■ MAX 7000B

■ MAX 7000S

■ Stratix IV

■ Stratix III

■ Stratix II

■ Stratix II GX

■ Stratix

■ Stratix GX

®

1K

®

®

10KA

®

II

III

®

®

®

device families:

II

®

Introduction

As design complexities increase, the use of vendor-specific intellectual
property (IP) blocks has become a common design methodology. Altera
provides parameterizable megafunctions that are optimized for Altera
device architectures. Using megafunctions instead of coding your own
logic saves valuable design time. Additionally, the Altera-provided
functions may offer more efficient logic synthesis and device
implementation. You can scale the size of the megafunction by setting
parameters.

Altera Corporation Confidential—Internal Use Only 1–1
May 2008 RAM Initializer (ALTMEM_INIT) Megafunction User Guide

Features

The HardCopy device family does not support the initialization of a
random-access memory (RAM) during power-up. The ALTMEM_INIT
megafunction addresses this need by providing memory initialization
functions for the HardCopy Stratix and HardCopy II devices. The
megafunction also supports Stratix devices that are migratable to
HardCopy devices, and in general, other Altera devices that come with
RAM.

The ALTMEM_INIT megafunction supports multiple RAMs. You can
add logic to the output data port of the megafunction to fan out to more
than one RAM. For example, if you want to initialize multiple RAMs to
contain all zeros, you can connect the appropriate output ports of the
ALTMEM_INIT megafunction to the RAMs that you want to initialize.

1 In this document, HardCopy devices refer to the

HardCopy Stratix and HardCopy II devices; Stratix devices
refer to the Stratix IV, Stratix III, Stratix II, and Stratix devices.

The ALTMEM_INIT megafunction initializes the RAM of a HardCopy
device with the content of a read-only memory (ROM). The ROM can be
located internally within the megafunction, or externally in an on-chip or
off-chip ROM. During initialization, the megafunction reads the content
of the ROM word-by-word and writes it to the RAM. The RAM can also
be initialized without the ROM, but the content can only be set to all
zeros.

1 Unless specified otherwise, external ROM refers to both on-chip

and off-chip ROM.

Features

The ALTMEM_INIT megafunction provides the following features to
implement memory initialization in HardCopy devices:

■ Support for RAM initialization using the INIT_FILE parameter

■ Support for RAM initialization from an external ROM with fixed

latency

■ Support for RAM initialization from an external ROM with variable

latency

■ Support for RAM initialization to all zeros

■ Status signal to indicate RAM initialization status

These features can be configured easily through the RAM Initializer

®

MegaWizard

Plug-In Manager.

f For more information about the INIT_FILE parameter, refer to

Chapter 3, Specifications.

1–2 Confidential—Internal Use Only Altera Corporation
RAM Initializer (ALTMEM_INIT) Megafunction User Guide May 2008

About this Megafunction

General Description

The main function of the ALTMEM_INIT megafunction is to copy the
content of a ROM into the RAM of a HardCopy device. The RAM can be
initialized in two modes—the internal-ROM or external-ROM mode. For
both modes, initialization begins when you assert the init signal.

In the internal-ROM mode, the RAM is initialized with the content of the
ROM in the ALTMEM_INIT megafunction. This mode uses only the

INIT_FILE parameter and does not require any connection to the
datain[] and rom_address[] ports.

In the external-ROM mode, the RAM is initialized from either an on-chip
or off-chip ROM. The datain[] and rom_address[] ports of the
megafunction must be connected to the external ROM. The initialization
process can be automated with a fixed latency by using the
ROM_READ_LATENCY parameter, or configured with a variable latency by
using the PORT_ROM_DATA_READY parameter and the
rom_data_ready control signal.

For the initialization of a RAM from an external ROM with fixed latency,
set the ROM_READ_LATENCY parameter to the number of delay cycles
incurred after the ALTMEM_INIT megafunction initiates a read from the
ROM. For example, if the ROM has both its input and output ports
registered, you can set the clock latency to 2 clock cyles. A fixed latency is
usually used for an external on-chip ROM where you can identify the
number of delay cycles.

For an off-chip ROM, you may not be able to identify the latency, or the
latency may vary for different ROMs. In such cases of variable latency,
you can use the PORT_ROM_DATA_READY parameter and the
rom_data_ready signal to control when to read data into the
megafunction.

The ALTMEM_INIT megafunction can also initialize a RAM without a
ROM, but the RAM content can only be set to all zeros. For such an
initialization, you do not need to use the INIT_FILE parameter or any
ROM ports.

The init_busy signal of the ALTMEM_INIT megafunction reflects the
initialization status. You can use this signal as an active-low signal to
enable the subsequent processes or as an indicator to show that memory
initialization is complete.

Altera Corporation Confidential—Internal Use Only 1–3
May 2008 RAM Initializer (ALTMEM_INIT) Megafunction User Guide

General Description

Figure 1–1 shows the block diagram of the input and output ports of the

ALTMEM_INIT megafunction.

Figure 1–1. Input and Output Ports of ALTMEM_INIT Megafunction

Figure 1–2 shows the block connections for the initialization of a

HardCopy device RAM using the INIT_FILE parameter. For this mode,
the ROM resides in the ALTMEM_INIT megafunction.

1 The block connections in Figure 1–2 also apply to RAM

initialization without a ROM.

Figure 1–2. Initializing RAM to All Zeros or with INIT_FILE Parameter

1–4 Confidential—Internal Use Only Altera Corporation
RAM Initializer (ALTMEM_INIT) Megafunction User Guide May 2008

About this Megafunction

Figure 1–3 shows the block connections for the initialization of a

HardCopy device RAM in the external-ROM mode. This mode uses an
external on-chip or off-chip ROM.

Figure 1–3. Initializing RAM with External ROM

Altera Corporation Confidential—Internal Use Only 1–5
May 2008 RAM Initializer (ALTMEM_INIT) Megafunction User Guide