Digital Voice Systems Net-2000-P25, Руководство пользователя

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Net-2000™ Voice Codec Unit
User’s Manual
Page 24
DVSI Confidential Proprietary
Section 4 – Net-2000™ VCU Interface Protocol
2 – 3 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 type
4 – 5 x x x x x x x x x x x x x x x x seq
6 – 7 0 0 0 0 0 0 0 0 1 1 0 0 0 0 1 x rate [0]
8 – 9 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 rate [1]
10 – 11 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 rate [2]
12 – 13 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 rate [3]
14 – 15 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 rate [4]
16 – 17 0 x 0 0 0 0 0 0 0 0 0 0 0 0 0 0 cmode
18 – 19 0 0 0 0 0 0 0 0 1 0 x x x x x x tone.idx
20 – 21 x 0 0 0 0 0 0 0 0 x x x x x x x tone.amp
22 – 23 0 0 0 0 0 0 0 0 1 0 x x x x x x ws
24 – 25 0 0 0 0 x x x x 0 0 0 x 0 0 x x format
26 – 27 x x x x x x x x x x x x x x x x voice [0]
28 – 29 x x x x x x x x x x x x x x x x voice[1]
30 – 31 x x x x x x x x x x x x x x x x voice [2]
… … … …
344 – 345 x x x x x x x x x x x x x x x x voice[159]
Table 18 Encode Packet
Voice packets have the following format described Table 18 and C-language data structure below:
struct voice_packet_t {
short len;
short type;
short seq;
short rate[5];
short cmode;
short tone[2];
short ws;
short format;
short voice[160];
};
The size of the Voice packet can vary depending on the number of samples in the
voice[]
buffer.
The actual number of elements in the
voice[]
buffer can vary between 159 and 161 for the APCO
Standard and Half-Rate vocoders. The nominal number of samples is 160. The
ws
and
len
elements of the Voice packet should be adjusted to indicate the actual number of samples in
voice[]
. The elements of the Voice packet are described in detail in the following sections.