Texas Instruments TMS320C80, TMS320C82 User Manual

TMS320C80 to TMS320C82
Software Compatibility

User’s Guide

1995 Digital Signal Processing Products

Printed in U.S.A., November, 1995
M418017-9741 revision

*

SPRU154

TMS320C80 to TMS320C82

Software Compatibility

User’s Guide

SPRU154

November 1995

Printed on Recycled Paper

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applicable at the time of sale in accordance with TI’s standard warranty . T esting and other quality
control techniques are utilized to the extent TI deems necessary to support this warranty.
Specific testing of all parameters of each device is not necessarily performed, except those
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TI SEMICONDUCTOR PRODUCTS ARE NOT DESIGNED, INTENDED, AUTHORIZED, OR
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Copyright  1995, Texas Instruments Incorporated

About This Manual

The TMS320C80 and the TMS320C82 are the first two members
of the ’C8x family of high-performance DSP devices. This guide
explains how to port software developed for one of these devices
to the other . It also presents a set of software compatibility guide­lines for developing software that will run on either device.

How to Use This Manual

Preface

Read This First

How to Use This Manual

This document contains three chapters that deal with different is­sues related to compatibility:

-

Chapter 1 discusses software-related differences between
the ’C80 and the ’C82.

-

Chapter 2 discusses guidelines and techniques for develop­ing software that can run on both the ’C80 and the ’C82.

-

Chapter 3 discusses guidelines and techniques for prototyp­ing ’C82 software using a ’C80.

If you need background information about the differences be­tween the ’C80 and the ’C82, read Chapter 1 before going on to
Chapter 2 and Chapter 3.

If you already understand the differences between the ’C80 and
the ’C82, then you can go directly to Chapter 2 and use Chapter 1
as reference material.

This user’s guide contains information at a general level to guide
you in completing programs. It does not discuss all issues related
to the ’C80 and the ’C82; use your best judgement in applying the
methods discussed in Chapter 2 and Chapter 3 to your applica­tion.

Related Documentation From Texas Instruments

Related Documentation From Texas Instruments

The following books describe the TMS320C8x and related support
tools. T o obtain a copy of any of these TI documents, call the T ex­as Instruments Literature Response Center at (800) 477–8924.
When ordering, please identify the book by its title and literature
number.

TMS320C80 Multimedia Video Processor Data Sheet

(literature number SPRS023) describes the features of the
’C80 device and provides pinouts, electrical specifications,
and timings for the device.

TMS320C8x System-Level Synopsis

(literature number
SPRU113) describes the ’C8x features, development
environment, architecture, memory organization, and
communication network (the crossbar).

TMS320C80 C Source Debugger User’s Guide

(literature

number SPRU107) describes the ’C8x master processor
and parallel processor C source debuggers. This manual
provides information about the features and operation of the
debuggers and the parallel debug manager; it also includes
basic information about C expressions and a description of
progress and error messages.

TMS320C80 Code Generation Tools User’s Guide

number SPRU108) describes the ’C8x code generation
tools. This manual provides information about the features
and operation of the linker, the master processor (MP) C
compiler and assembler, and the parallel processor (PP) C
compiler and assembler. It also describes the common
object file format (COFF) and shows you how to link MP and
PP code.

(literature

TMS320C80 Master Processor User’s Guide

number SPRU109) describes the ’C8x master processor
(MP). This manual provides information about the MP
features, architecture, operation, and assembly language
instruction set; it also includes sample applications that
illustrate various MP operations.

TMS320C80 Multitasking Executive User’s Guide

number SPRU112) describes the ’C8x multitasking execu­tive software. This manual provides information about the
multitasking executive’s software features, operation, and
interprocessor communications. It also includes a list of task
error codes.

iv

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

(literature

(literature

Related Documentation From Texas Instruments / If You Need Assistance

TMS320C80 Parallel Processor User’s Guide

ber SPRU110) describes the ’C8x parallel processor (PP).
This manual provides information about the PP features, ar­chitecture, operation, and assembly language instruction
set. It also includes software applications and optimizations.

TMS320C80 Transfer Controller User’s Guide

ber SPRU105) describes the ’C80 transfer controller (TC).
This manual provides information about the TC features,
functional blocks, and operation. It also includes examples
of block-write operations for big- and little-endian modes.

TMS320C80 Video Controller User’s Guide

SPRU111) describes the ’C80 video controller (VC). This
manual provides information about the VC features, archi­tecture, and operation. It also includes procedures and ex­amples for programming the serial register transfer (SRT)
controller and the frame timer registers.

If You Need Assistance. . .

If you want to. . . Do this. . .

Request more information
about Texas Instruments
Digital Signal Processing
(DSP) products

Order Texas Instruments
documentation

Ask questions about product
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problems

Report mistakes in this
document or any other TI
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Call the CRC† hotline:

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Or write to:
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Call the CRC† hotline:

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Call the DSP hotline:

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Fill out and return the reader response
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P.O. Box 1443
Houston, Texas 77251–1443

Read This First

v

vi

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

Contents

Contents

1 Comparison of the ’C80 and ’C82 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Describes differences between the ’C80 and ’C82 that af fect software compatibility.

1.1 Overview of ’C80 and ’C82 Features 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.2 Parallel Processor Differences 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.3 Transfer Controller Differences 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.3.1 Number of Externally Initiated Packet Transfer Requests 1-4. . .

1.3.2 RAM Bank Configuration Mechanisms 1-4. . . . . . . . . . . . . . . . . . .

1.4 Video Controller Differences 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5 Memory Differences 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.1 Data RAMs 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.2 Parameter RAMs 1-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.3 Caches 1-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 Programming for Compatibility 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Provides techniques for programming ’C80/’C82-compatible software.

2.1 Programming Considerations 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2 Obtaining Device-Specific Information 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2.1 Determining the Device that is Executing your Software (MP) 2-3.

2.2.2 Determining the Device that is Executing your Software (PP) 2-3. .

2.2.3 Initializing a PP’s Stack Pointer 2-4. . . . . . . . . . . . . . . . . . . . . . . . . .

2.2.4 Counting the Number of PPs 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3 Technique #1: Using Only Common RAM 2-6. . . . . . . . . . . . . . . . . . . . . . . .

2.3.1 Advantages of Technique #1 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3.2 Disadvantages of Technique #1 2-6. . . . . . . . . . . . . . . . . . . . . . . . .

2.3.3 Implementing Technique #1 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3.4 Considerations When Using Technique #1 2-7. . . . . . . . . . . . . . . .

2.4 Technique #2: Using Pointers to Allocate RAM 2-8. . . . . . . . . . . . . . . . . . .

2.4.1 Advantages of Technique #2 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4.2 Disadvantages of Technique #2 2-8. . . . . . . . . . . . . . . . . . . . . . . . .

2.4.3 Implementing Technique #2 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4.4 Considerations When Using Technique #2 2-9. . . . . . . . . . . . . . . .

Contents

vii

Contents

3 Prototyping ’C82 Code on the ’C80 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Describes techniques for emulating the ’C82’s RAM with the ’C80’s RAM.

3.1 Overview 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.2 Emulating the ’C82’s Data RAMs 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.2.1 Emulating the ’C82’s PP0 Data RAM 0 and PP1 Data RAM 0 3-3.

3.2.2 Emulating the ’C82’s PP0 Data RAM 1 and PP1 Data RAM 1 3-3.

3.3 Emulating the ’C82’s Parameter RAMs 3-4. . . . . . . . . . . . . . . . . . . . . . . . . .

3.3.1 Emulating the PP Parameter RAMs 3-4. . . . . . . . . . . . . . . . . . . . . .

3.3.2 Emulating the MP Parameter RAM 3-5. . . . . . . . . . . . . . . . . . . . . .

3.4 Prototyping Code Using Linker Command Files 3-6. . . . . . . . . . . . . . . . . .

3.4.1 PP-Relative Addressing 3-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.4.2 Map Files 3-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.4.3 Linking Your ’C82 Code for Prototyping on a ’C80 3-7. . . . . . . . .

3.4.4 Linking your Code for a ’C82 3-11. . . . . . . . . . . . . . . . . . . . . . . . . . .

3.4.5 MP Linker Command Files 3-14. . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.4.6 Considerations when Using Linker Command Files 3-15. . . . . . .

A The ’C80 and ’C82 Memory Maps A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Provides ’C80 and ’C82 memory maps.

viii

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

Contents

Figures

1–1 ’C80 and ’C82 Data RAMs in the Memory Map 1-7. . . . . . . . . . . . . . . . . . . . . .

1–2 ’C80 and ’C82 Parameter RAMs in the Memory Map 1-9. . . . . . . . . . . . . . . . .

1–3 ’C80 and ’C82 MP Parameter RAM Block Diagram 1-10. . . . . . . . . . . . . . . . .

1–4 ’C80 and ’C82 PP Parameter RAM Block Diagram 1-11. . . . . . . . . . . . . . . . . .

1–5 PP State Information on the Stack at Reset 1-12. . . . . . . . . . . . . . . . . . . . . . . .

2–1 The Type Field in the MP config Register 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . .

2–2 The PP’s comm Register 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2–3 Structure of a PP Command Buffer 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1 TMS320C80 Memory Map A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–2 TMS320C82 Memory Map A-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents

ix

Contents

Examples

2–1 Initializing a PP’s Stack Pointer and Comm registers 2-4. . . . . . . . . . . . . . . . .

2–2 MP C Function for Counting the Number of PPs 2-5. . . . . . . . . . . . . . . . . . . . .

3–1 Sample PP C Program 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–2 ’C80 PP Linker Command File for example.c 3-10. . . . . . . . . . . . . . . . . . . . . .

3–3 ’C80 Map File Lines for Vector A and Vector B 3-11. . . . . . . . . . . . . . . . . . . . .

3–4 ’C82 PP Linker Command File 3-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–5 ’C82 Map File Lines for Vector A and Vector B 3-13. . . . . . . . . . . . . . . . . . . . .

3–6 ’C80 MP Linker Command File 3-14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–7 ’C82 MP Linker Command File 3-15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–8 Sample PP C Program With an Assembly Language Function 3-17. . . . . . . .

3–9 Assembly Language Function to Calculate the Dot Product of 3-18. . . . . . . .

Two Vectors

x

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

Running Title—Attribute Reference

Contents

4 Comparison of the ’C80 and ’C82 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Describes differences that affect compatibility in the ’C80 and ’C82.

1.1 Overview of ’C80 and ’C82 Features 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.2 Parallel Processor Differences 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.3 Transfer Controller Differences 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.3.1 Number of Externally Initiated Packet Transfer (XPT) Requests1­4

1.3.2 RAM Bank Configuration Mechanisms 1-4. . . . . . . . . . . . . . . . . . .

1.4 Video Controller Differences 1-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5 Memory Differences 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.1 Data RAMs 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.2 Parameter RAMs 1-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1.5.3 Caches 1-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 Programming for Compatibility 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Provides techniques for programming ’C80/’C82-compatible software.

2.1 Programming Considerations 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2 Obtaining Device-Specific Information 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . .

2.2.1 Determining the Device that is Executing your Software (MP) 2-3

2.2.2 Determining the Device that is Executing your Software (PP) 2-3

2.2.3 Initializing a PP’s Stack Pointer 2-4. . . . . . . . . . . . . . . . . . . . . . . . . .

2.2.4 Counting the Number of PPs 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3 Technique #1: Using Only Common RAM 2-6. . . . . . . . . . . . . . . . . . . . . . . .

2.3.1 Advantages 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3.2 Disadvantages 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3.3 Implementing Technique #2 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.3.4 Considerations 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4 Technique #2: Using Pointers to Allocate RAM 2-8. . . . . . . . . . . . . . . . . . .

2.4.1 Advantages 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4.2 Disadvantages 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4.3 Implementing Technique #2 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2.4.4 Considerations 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter Title—Attribute Reference

xi

Contents

6 Prototyping ’C82 Code on the ’C80 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Describes techniques for emulating the ’C82’s RAM with the ’C80’s RAM.

3.1 Overview 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.2 Emulating the ’C82’s Data RAMs 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3.2.1 Emulating the ’C82’s Data RAM 0 3-3. . . . . . . . . . . . . . . . . . . . . . .

3.2.2 Emulating the ’C82’s PP0 Data RAM 1 and PP1 Data RAM 1 3-3

3.3 Emulating the ’C82’s Parameter RAMs 3-4. . . . . . . . . . . . . . . . . . . . . . . . . .

3.3.1 Emulating the PP Parameter RAMs 3-4. . . . . . . . . . . . . . . . . . . . . .

3.3.2 Emulating the MP Parameter RAM 3-5. . . . . . . . . . . . . . . . . . . . . .

3.3.3 Managing Pointers 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

B The ’C80 and ’C82 Memory Maps A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Provides the memory maps of the ’C80 and ’C82.

xii

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

Running Title—Attribute Reference

Figures

1–1 ’C80 and ’C82 Data RAMs in the Memory Map 1-7. . . . . . . . . . . . . . . . . . . . . .

1–2 ’C80 and ’C82 Parameter RAMs in the Memory Map 1-9. . . . . . . . . . . . . . . . .

1–3 ’C80 and ’C82 MP Parameter RAM Block Diagram 1-10. . . . . . . . . . . . . . . . .

1–4 ’C80 and ’C82 PP Parameter RAM Block Diagram 1-11. . . . . . . . . . . . . . . . . .

1–5 PP State Information on the Stack at Reset 1-12. . . . . . . . . . . . . . . . . . . . . . . .

2–1 The Type Field in the MP config Register 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . .

2–2 The PP’s comm Register 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2–3 Structure of a PP Command Buffer 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3–1 Structure of a PP Command Buffer 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–1 TMS320C80 Memory Map A-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A–2 TMS320C82 Memory Map A-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Contents

xiii

xiv

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

Chapter 1

Comparison of the ’C80 and ’C82

There are several differences between the ’C80 and the ’C82. As
a programmer, you must be aware of these dif ferences to ef fec­tively write code that runs on both the ’C80 and the ’C82. This
chapter describes important differences to prepare you for the
software-related discussions in Chapter 2 and Chapter 3.

In this chapter, you will find information that will help you:

-

Understand general differences between the ’C80 and ’C82.

-

Understand memory differences between the ’C80 and ’C82.

-

Understand the basis for the information in Chapter 2 and
Chapter 3.

Topics

1.1 Overview of ’C80 and ’C82 Features 1-2. . . . . . . . . . . . . .

1.2 Parallel Processor Differences 1-3. . . . . . . . . . . . . . . . . . .

1.3 Transfer Controller Differences 1-4. . . . . . . . . . . . . . . . . . .

1.4 Video Controller Differences 1-5. . . . . . . . . . . . . . . . . . . . .

1.5 Memory Differences 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chapter Title—Attribute Reference

1-1

Overview of ’C80 and ’C82 Features

1.1 Overview of ’C80 and ’C82 Features

The ’C80 offers processing power equivalent to up to 2 billion
RISC operations/second. The ’C82 is a low-cost implementation
of the ’C8x architecture that provides high levels of processing
power for cost-sensitive applications.

The ’C80 and the ’C82 are very similar in design. They have sev­eral features in common, including a crossbar network, parallel
processors, a master processor, a transfer controller, and on­chip RAM. The processors are binary compatible and can run
each other’s software if the software is written for compatibility.
Four main differences relate to compatibility:

-

The ’C80 has four parallel processors; the ’C82 has two.

-

The on-chip RAM of the ’C80 is divided into 25 2-KB blocks;
the on-chip RAM of the ’C82 is divided into 11 4-KB blocks.

-

The ’C80 transfer controller has 7 externally initiated packet
transfer (XPT) requests; the ’C82 transfer controller has 15.

-

The ’C80 has an on-chip video controller; the ’C82 has none.

Table 1–1 compares the features of the ’C80 and the ’C82.

Table 1–1.’C80 and ’C82 Features

Feature ’C80 ’C82

Number of PPs 4 2
On-chip video controllers 1 None
Total on-chip RAM 50 KB 44 KB
Local data RAM per PP 6 KB 8 KB
Parameter RAM per PP 2 KB 4 KB
PP instruction cache size 2 KB 4 KB
MP parameter RAM size 2 KB 4 KB
MP data cache size 4 KB 4 KB
MP instruction cache size

4 KB 4 KB

1-2

TMS320C80 to TMS320C82 Software Compatibility User’s Guide

1.2 Parallel Processor Differences

The most important difference related to the parallel processors
(PPs) is the number of PPs per chip: the ’C80 has four PPs and
the ’C82 has two.

Since the ’C82 has two PPs, software written to execute on both
the ’C80 and ’C82 must not require more than two PPs. Software
that can use up to four PPs but that requires only two PPs will run
on both devices.

The number of PPs on a chip can be counted through software.
This allows you to optimize your software’s use of available PPs.
See subsection 2.2.4,
tion of how your software can determine the number of available
PPs.

Counting the Number of PPs

Parallel Processor Differences

, for a descrip-

Comparison of the ’C80 and the ’C82

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Transfer Controller Differences

1.3 Transfer Controller Differences

The differences between the transfer controllers (TCs) on the
’C80 and ’C82 are hardware differences. Generally , these differ­ences have a negligible impact on how you write your software.

The ’C82 and ’C80 TCs differ in two main ways:

-

The ’C80 TC supports 7 XPT requests, but the ’C82 TC sup­ports 15 XPT requests.

-

The ’C80 TC uses dedicated pins for obtaining memory con­figuration information, but the ’C82 TC uses a configuration
cache.

1.3.1 Number of Externally Initiated Packet Transfer Requests

The number of XPT requests handled by the ’C80 and ’C82 is dif­ferent. However, because XPT requests are driven by external
devices, the seven XPT requests shared by the ’C80 and ’C82
generally aren’t used to emulate each other in different systems
with different peripherals. For example, the likelihood is small
that the peripheral connected to XPT1 on the ’C80 software de­velopment board (SDB) is the same as the peripheral connected
to XPT1 on a target ’C82 board. XPTs are normally handled
through software drivers that are written for each application. The
drivers for the SDB will almost always differ from the drivers used
in an actual application.

1.3.2 RAM Bank Configuration Mechanisms

The special RAM bank configuration pins on the ’C80 and the
configuration cache on the ’C82 are hardware features that have
a negligible impact on software.

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TMS320C80 to TMS320C82 Software Compatibility User’s Guide