Version: 1.18
PRELIMINARY/CONFIDENTIAL
TrueSpeech® Co-Processor
9.13
Playback & Record Buffer Control
9.13.1
Monitoring Buffer Depth
The buffer monitoring commands for the record and playback channels return the number of frames currently present
in the respective receive and transmit queues. Each frame corresponds to 30ms of speech (assuming the base frame
size is set to 240). The Host uses these commands for buffer management purposes. The frame count does not
include data held in the Host interface transmit or receive data buffer registers.
RECORD:
Read Buffer Depth
Command:
Status:
5112H
the number of record frames currently in the receive buffer.
PLAYBACK:
Read Buffer Depth
Command:
Status:
5212H
the number of playback frames currently in the transmit buffer.
9.13.2
Speech Frame Create
The frame create command creates an additional speech frame in the transmit or receive buffer, if the buffer is not
full. Copying the most recent frame in the buffer creates the frame.
RECORD:
Create Record Frame:
Status:
5117H
0 or 1
The number of frames created. If the buffer is full thestatus reply will be 0.
If the buffer is not full, and the frame can be created, the status reply will be 1.
PLAYBACK:
Create Playback Frame: 5217H
Status: 0 or 1
The number of frames created. If the buffer is full the status reply will be 0.
If the buffer is not full, and the frame can be created, the status reply will be 1.
Note: For playback, the G.723.1/TrueSpeech 6.3, 5.3, 4.8 and 4.1 rates include a built-in frame creation
mechanism that is activated using a specially encoded speech playback frame. This mechanism
allows replacement of a dropped or corrupted speech frame by extrapolation of speech data from
previous frames. Refer to Section 9.8.7 for information regarding frame erasure.
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SANTA CLARA, CA 95054 PH: 408 986 – 4300 FAX: 408 986 – 4490
95
All specifications are subject to change without prior notice.
ETC [ ETC ]
