Digital Voice Systems AMBE-20X0 HDK, Руководство пользователя

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AMBE-20x0™-HDK Development Board
User’s Manual
(Preliminary)
Page 20
DVSI Confidential Proprietary
Section 4 – Communication via Channel Interface
Compressed Voice
Bit Rate Compressed voice
Number of data bits Total Packet Length
(Number of channel data
words including sync word)
2000 40 4
2400 48 4
3000 60 5
3600 72 6
4000 80 6
4200 84 7
4400 88 7
4800 96 7
7200 144 10
8000 160 11
9600 192 13
Table 19 Example Packet Size for Various Compresssed Voice Data Rates
Data Structure “AMBE-2000 Format” Packet
The data structure in AMBE-2000 format contain the all 24 16-bit words that are output from the AMBE-
2000™ vocoder packet as describe in the AMBE-2000™ vocoder chip users Manual. The HDK can only
enter into AMBE-2000 format by using the console monitor and selecting the “B” option and then the “1”
optionfrom the command menus. All setting in AMBE-2000 format are stored in volatile memory an are
not save after a board reset or a power cycle.
Word # Description
0 Header always set to 0x13EC
1 Power Control ID (8bits) Control Word 1 (8 bits) – see Table 5-B
2 Rate info 0
3 Rate info 1
4 Rate info 2
5 Rate info 3
6 Rate info 4
See Tables 5-C and 5-D
7 Unused in Input
8 Unused in Input
9 Unused in Input
10 DTMF Control – see Tables 5-E and 5-F
(1
2
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11 Control Word 2 – see Table 5-G
12 Channel Data
13 Channel Data
14 Channel Data
15 Channel Data
16 Channel Data
17 Channel Data
18 Channel Data
19 Channel Data
20 Channel Data
21 Channel Data
22 Channel Data
2
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23 Channel Data