ISD-T360 ETC [List of Unclassifed Manufacturers], ISD-T360 Datasheet - Page 91

• Manufacturer Part Number: ISD-T360
• Description: VoiceDSP Digital Speech Processor with Master/Slave, Full-Duplex Speakerphone, Multiple Flash and ARAM/DRAM Support
• Manufacturer: ETC [List of Unclassifed Manufacturers]

If the current vocabulary is undefined, ERR_INVALID is reported.
Example
TUNE
Sets the value of the tunable parameter identified by index (one byte) to the 2-byte value,
parameter_value . This command may be used to tune the DSP algorithms to a specific Data Access
Arrangement (DAA) interface, or to change other parameters. If you do not use TUNE, the VoiceDSP
processor uses default values.
If index does not point to a valid tunable parameter, ERR_PARAM is set in the error word.
NOTE
The following tables 2-4 to 2-11 describe the tunable parameters, their index numbers and their default
values, grouped by their functionality.
ISD
SW 02 00 00
Byte sequence:
Description:
4
5
6
Index
The tunable parameters are assigned with their default values on application of power. The INIT
command does not affect these parameters.
Table 2-4: TUNABLE PARAMETERS: Voice Compression and Decompression (VCD)
Voice Activity
Detection (VAD):
VAD_SIL_THRESHOLD
Voice Activity
Detection (VAD):
VAD_SIL_THRESHOLD_ST
EP
Voice Activity
Detection (VAD):
VAD_SIL_BURST_THRESH
OLD
Parameter Name
Microcontroller
VoiceDSP
Announce the first word, in the word table of the currently selected vocabulary, twice.
Tune index parameter_value
Prevents speech from being interpreted as silence. The silence
detection algorithm has an adaptive threshold, which is
changed according to the noise level. This parameter is,
therefore, only the initial threshold level.
Legal values: 9216 to 13824 in 512 (6 dB) steps.
Defines the adaptive threshold changes step.
If this threshold is too low, the threshold converges too slowly. If
it is too high, silence detection is too sensitive to any noise.
Legal values: 3 to 48.
The minimum time period for speech detection, during
silence. As this threshold increases, the time period
interpreted as silence increases.
If this threshold is too low, a burst of noise is detected as
speech. If it is too high, words may be partially cut off.
Legal values: 1 to 3.
Description
21
21
02
02
00
00
11264
12
2
Default
00
00
2-51