NSAM265SR Datasheet, PDF (11/58 Pages) National Semiconductor (TI) – CompactSPEECH Digital Speech Processors

1 0 Theory of Operation (Continued)
1 9 3 External (International) Vocabularies
Tools for creation of external vocabularies are available
With these tools voice format files can be compressed and
both numbers and sentences can be composed to comply
with the grammar of a specific language
The CompactSPEECH supports external vocabularies
which you can easily tailor for country-specific applications
Every language has its own sentence structure and its own
mechanism for composing numbers Therefore the informa-
tion on the sentence structure and number composition is a
part of the external vocabulary A method IVS has been
developed which uses this information to compose a com-
plete sentence
The information stored in the external vocabulary together
with this retrieval method can be used to compose sen-
tences or phrases in various languages or to implement a
voice menu or command voice prompts The additional vo-
cabulary can reside on either external ROM or
(NSAM265SF only) AFLASH
IVS enables you to have the same program on the controller
to support operation with several languages You have only
to switch to another table containing another language and
the machine ‘‘speaks’’ the new language
The Rule
Before using a specific table set the currently used vocabu-
lary with the command SV (Set Vocabulary Type) Until the
next invocation of this command the selected vocabulary is
used when invoking any synthesis command
IVS Structure
It is possible to have several vocabularies on one external
ROM or FLASH device and the controller can switch be-
tween them
1 10 INITIALIZATION
Use the following procedures to initialize the Compact-
SPEECH processor
Normal Initialization
1 Reset the CompactSPEECH by activating the RESET sig-
nal (See Section 2 2 )
2 Issue a GSW command and check that the EV RESET
bit in the status word is set
3 Issue a GCFG (Get Configuration) command to figure out
what CompactSPEECH knows about your environment
4 Issue a CFG (Configure CompactSPEECH) command to
change the configuration according to your environment
5 Issue an INIT (Initialize System) command to initialize the
CompactSPEECH
6 Issue a GMS (Get Memory Status) command to deter-
mine the size of the memory
(Optional NSAM265SF only) Issue an FR command to
free potentially available memory
7 Issue a AMAP (Check and Map ARAM) 3 command to
test and map the ARAM (Required only on NSAM265SR)
8 Use the TUNE command to set all hardware parameters
Production Test (for the NSAM265SR only)
To save time on the production line of the final product a
set of diagnostics is available Production testing is the pri-
mary use of the AMAP command
The following procedure is recommended
1 Reset the CompactSPEECH by activating the RESET sig-
nal (See Section 2 2 )
2 Issue a GSW command and check that the EV RESET
bit in the status word is set
3 Issue a GCFG (Get Configuration) command to figure out
what CompactSPEECH knows about your environment
4 Issue a CFG (Configure CompactSPEECH) command to
change the configuration according to your environment
5 Issue an INIT command
6 Issue a AMAP 0 command to verify that the correct num-
ber of ARAMs are connected
7 Issue a AMAP 1 command as part of the tests to verify
connectivity to all ARAMs
8 Record and playback a short message (up to 5 seconds)
as part of the tests to verify connectivity and functionality
of the codec interface
9 If you use an external vocabulary choose the appropriate
table and playback a synthesized sentence (e g ‘‘You
have no messages ’’) as part of the tests to check con-
nectivity to the ROM(s) holding the External vocabulary
2 0 Functional Description
2 1 INTRODUCTION
This section provides details of the functional characteris-
tics of the CompactSPEECH processor It is divided into the
following sections
Resetting
The serial interface
Codec interface
Memory (DRAM FLASH) accesses
Memory (DRAM FLASH) configurations
IVS access
Clocking
Power-down mode
Power and grounding
The processor signals mentioned in this section are de-
scribed in Appendix A
2 2 RESETTING
The RESET pin is used to reset the CompactSPEECH proc-
essor
On application of power RESET must be held low for at
least 30 ms after V_CC is stable This is to ensure that all on-
chip voltages are completely stable before operation
Whenever RESET is applied it must also remain active for
not less than 30 ms During these 30 ms and for 100 ms
after the TST signal must be high This can be done by
putting a pull-up resistor on the WRO TST pin
The value of MWRDY is undefined during the 30 ms reset
period and for 100 ms after The microcontroller should ei-
ther wait before polling the signal for the first time or the
signal should be pulled high during this period
Upon reset the ENV0 signal is sampled to determine the
operation environment During reset the EMCS ENV0 pin is
used for the ENV0 input signals An internal pull-up resistor
sets ENV0 to 1
After reset the same pin is used for EMCS
System Load on ENV0
The load connected to the ENV0 pin should not allow the
voltage on ENV0 to drop below V_ENVh
If the load caused by the ENV0 pin exceeds 10 mA use an
external pull-up resistor to keep the pin at 1
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