Texas Instruments MSP53C691 User manual

MSP53C691 Speech
Synthesizer
December 2000 MSDS Speech
User’s Guide
SPSU020

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accordance with TI’s standard warranty. Testing and other quality control techniques are utilized to the extent
TIdeemsnecessarytosupport thiswarranty. Specifictestingofallparameters ofeachdevice isnotnecessarily
performed, except those mandated by government requirements.
Customers are responsible for their applications using TI components.
In order to minimize risks associated with the customer’s applications, adequate design and operating
safeguards must be provided by the customer to minimize inherent or procedural hazards.
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Copyright 2000, Texas Instruments Incorporated

How to Use This Manual
iii
Read This First
Preface
Read This First
About This Manual
This user’s guide provides information on the MSP53C691 mixed signal pro-
cessor. This information includes architecture overview, detailed architecture
description, assembly language instruction set, code development tools, and
customer information.
How to Use This Manual
This document contains the following chapters:
- Chapter 1—Introduction
- Chapter 2—MSP53C691 Hardware Description
- Chapter 3—MSP53C691 Software Description
- Chapter 4—MSP53C691 Timing Considerations
- Appendix A—Designing the Master Microcontroller Software
- Appendix B—FM Synthesis
- Appendix C—Editing Tools and Data Preparation
- Appendix D—Pitch and Speech Shifting for 6xx MELP
- Appendix E—Guidelines for Optimal TI Speech

Related Documentation From Texas Instruments
iv
Information About Cautions
This book contains cautions.
This is an example of a caution statement.
A caution statement describes a situation that could potentially
damage your software or equipment.
The information in a caution is provided for your protection. Please read each
caution carefully.
Related Documentation From Texas Instruments
SPSS023B Data sheet, MSP50C614
SPSU014 User’s guide, MSP50C614
SPSS028A Data sheet, MSP50C604
SPSU014 User’s guide, MSP50C604

Running Title—Attribute Reference
v
Chapter Title—Attribute Reference
Contents
1 Introduction 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Description 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Features 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 MSP53C691 Device 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Pin Assignments and Description 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 DAC Information 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Algorithms Supported 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 MSP53C691 Hardware Description 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 MSP53C691 Interface Overview 2-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Microprocessor Interface Description 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.1 4-Bit Mode 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2.2 8-Bit Mode 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Read Operation by the Master 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.4 Write Operation by the Master 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 MSP53C691 Device Initialization 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.6 Microprocessor Interface Timing 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 MSP53C691 Software Description 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Software Overview 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Commands and Data Streams 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Sequence of Command Codes and Data Streams 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.1 Command Header 3-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.2 Parameters 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.3 Return Values 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Command Codes 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5 Description of the Command Codes 3-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.1 Command Header 1—Configure Internal Registers 3-8. . . . . . . . . . . . . . . . . . . . . .
3.5.2 Command Header 2—Set/Clear I/O Ports, PD4 Through PD7 3-10. . . . . . . . . . . .
3.5.3 Command Header 3—Read Contents of I/O Ports 3-11. . . . . . . . . . . . . . . . . . . . . .
3.5.4 Command Header 4—Start Speaking 3-13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.5 Command Header 5—Stop Speaking 3-29. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.6 Command Header 6—Adjust the Volume 3-31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.7 Command Header 7—Return Buffer Status 3-32. . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.8 Command Header 8—Initiate Sleep 3-32. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.9 Command Header 9—Receive FM Data 3-33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.5.10 Command Header A—Perform Speed Shift or Pitch Shift 3-33. . . . . . . . . . . . . . . .
4 MSP53C691 Timing Considerations 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 General Constraints 4-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Running Title—Attribute Reference
vi
4.2 MSP53C391 Timing Waveforms 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.1 CELP/MELP 4-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2.2 MIX Mode 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A Designing the Master Microcontroller Software A-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B FM Synthesis B-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
C Editing Tools and Data Preparation C-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D Pitch and Speed Shifting for 6xx MELP D-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
E Guidelines for Optimal TI Speech E-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Figures
1–1 MSP53C691 Pin Assignments 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–1 MSP53C691 Interfacing Diagram—4-Bit Mode 2-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–2 MSP53C691 Interfacing Diagram—8-Bit Mode 2-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–3 Data Transfer—Read 2-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–4 Data Transfer—Write 2-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–5 MSP53C691 RESET Diagram 2-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–6 Device Initialization 2-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2–7 Oscillator and PLL Connection 2-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4–1 MSP53C691 Hardware Interface Connection 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A–1 Program Flow for the Master Main Routine A-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A–2 Program Flow for an ISR Tied to the Falling Edge of OUTRDY A-4. . . . . . . . . . . . . . . . . . . . . .
A–3 Program Flow for an ISR Tied to the Falling Edge of INRDY to Play Mixed Mode A-5. . . . . .
A–4 Routine for Sending Data or Commands to the Slave A-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
A–5 Program Flow for ISR Tied to the Falling Edge of INRDY to Play CELP/MELP Only A-7. . . .
B–1 FM Conversion Process B-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Tables
1–1 MSP53C691 Signal Description 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3–1 Command Codes 3-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B–1 Command Summary B-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D–1 Pitch Control D-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
D–2 Speed Shifting Summary D-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1-1
Introduction
Introduction
This chapter briefly describes the features, hardware, and software of the
MSP53C691 speech synthesizer.
Topic Page
1.1 Description 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Features 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 MSP53C691 Device 1-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.4 Pin Assignments and Description 1-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.5 D/A Information 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.6 Algorithms Supported 1-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1

Description
1-2
1.1 Description
TheMSP53C691isa standard slave synthesizer fromTexasInstrumentsthat
accepts compressed speech data from other microprocessors/microcontrol-
lers and converts it to speech. This allows the TI MSP53C691 to be used with
a master microprocessor/microcontroller in various speech products, includ-
ing electronic learning aids, games, and toys. (When referring to the
MSP53C691 device in this guide, the terms slave and MSP53C691 are used
interchangeably, and the terms master and microcontroller are used inter-
changeably.)
The MSP53C691 supports several speech synthesis algorithms to permit
tradeoffs that meet the price performance requirements of different markets.
It also incorporates a single-channel FM synthesis routine for music genera-
tioncombinedwithcodebook-exitedlinear-predictive(CELP)codingormixed-
excitation linear prediction (MELP) coding.
The MSP53C691 is a special program that runs on the MSP50C604 device.
FormoreinformationabouttheMSP50C604,please refertothelatest version
of the MSP50C604 data sheet (literature number SPSS28A) and to the
M
SP50x6x User’s Guide (literature number: SPSU014).
1.2 Features
- The device incorporates a wide range of algorithms on one chip. This
rangeallowsusersto choose fromlowbitratetohigh-quality synthesizing
routines for their application. The following algorithms are included:
J MELP v 3.4 1.0 kbps—3.5 kbps (at 8 Khz sampling rate)
J CELP v3.4 3.0 kbps, 3.7 kbps, 4.5 kbps, 6.2 kbps, 7.7 kbps, and
11.2 kbps (at 8 kHz sampling rate)
J ADPCM
J Single-channel FM synthesis
J Single-channel FM with CELP or MELP (mixed mode)
- Six-level digital gain control
- Interrupt-driven data transfer for speech or command
- Four customer-configurable I/Os
- Option for four- or eight-bit data bus
J Eight-bit data bus with four control lines
J Four-bit data-bus with five control lines
- Low power (less than 10 µA) sleep mode for long battery life
J Three different sleep modes

MSP53C691 Device
1-3
Introduction
- A choice of oscillator control
J Theinternaloscillatorcanbecontrolledwitha1%resistorforlowcost,
or a standard 32.768-kHz crystal for higher precision.
- Speed and pitch shifting in MELP
- Stops speaking at any time (only in 4-bit mode)
- Supports sending commands to perform certain tasks while speaking
(only in 4-bit mode)
- Operating voltage 3 V–5.2 V
- Direct speaker drive, 32 Ω
- Available in die form or 64-pin LQFP package option
1.3 MSP53C691 Device
TheMSP53C691isoptimizedtosupportafour-bit-widedatatransferprotocol.
The MSP53C691 has two status bits and three control bits which control the
communication protocol between the master and the slave. The MSP53C691
also has one bit (data/command) which differentiates between command or
speech data feeding into the slave.
The MSP53C691 also supports the 8-bit wide data transfer but support for
commands is disabled. Switching between 4-bit mode or 8-bit mode is per-
mitted between speech data files.
MSP53C691
(4-bit mode) MSP53C691 (8-bit mode)
Number of data lines 4 8
Number of control lines 3 (strobe, R/W, data/command) 2 (strobe, R/W)
Number of status lines 2 (INRDY, OUTRDY) 2 (INRDY, OUTRDY)
Number of general-purpose I/O lines 4 4
Support for commands (while speaking) Yes No

Pin Assignments and Description
1-4
1.4 Pin Assignments and Description
Figure 1–1 shows the pin assignments for the MSP53C691. Table 1–1 pro-
vides pin functional descriptions.
Figure 1–1.MSP53C691 Pin Assignments
1718 19
VSS
DACP
VDD
DACM
VDD
PD4
PD5
PD6
PD7
DATA0
DATA1
DATA2
DATA3
DATA/COMMAND (DATA4)
DATA5
DATA6
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
20
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
VDD
VDD
R/W
STROBE
OUTRDY
INRDY
TEST
SCANOUT
SYNC
SCANCLK
SCANIN
RESET
PLL
OSCIN
OSCOUT
VSS 21 22 23 24
NC NC
63 62 61 60 5964 58
NC NC NC NC NC NC NC
NC NC NC NC NC
NC NC NC NC NC NC
56 55 5457
25 26 27 28 29
53 52
NC
NC NC
51 50 49
30 31 32
NC
DATA7
NC NC NC
NC
MSP53C691
PM PACKAGE
(TOP VIEW)
VDD
VSS VSS
NC – No internal connection
NOTE: Pin 35 is DATA4 in 8-bit mode, or DATA/COMMAND in 4-bit mode.
Table 1–1.MSP53C691 Signal Description
NAME PIN
NO. PAD NO. I/O DESCRIPTION
INRDY 6 6 O An output signal from the slave to the microcontroller. A low signal
indicates that the MSP53C691 is ready to accept data or
command. A high signal indicates that the MSP53C691 is busy
and the microcontroller must not write any data or command to it.
OUTRDY 5 5 O An output signal from the slave to the microcontroller. A low signal
indicates that the MSP53C691 is ready to send data or command
to the microcontroller.
STROBE 4 4 I An input signal to the slave from the microcontroller. STROBE
sequences read or write operations in conjunction with the R/W
signal. This signal is pulsed high-low-high for read or write
operations sequencing.
R/W 3 3 I An input signal to the slave from the microcontroller. Read/write
select signal which is set high for read operations or set low for
write operations by the microcontroller.