Digital Voice Systems AMBE-2020, Руководство пользователя

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AMBE-2000™ Vocoder Chip Users Manual
Version 4.92, June, 08
DVSI Confidential Proprietary, Subject to Change Page 29
Visit us at www.dvsinc.com
Figure 5-A Basic Framed Input Format
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
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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
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23 Channel Data
5.2.1 Framed Input: Word 0 : Header
The decoder uses the header information to synchronize with the beginning of each 20 millisecond frame. this 16 bit word
MUST be 0x13EC.
5.2.2 Framed Input: Word 1 : Power Control ID
Set the 8-bit Power Control ID field to 0x00 for normal use. For Power Down Mode, set this value to 0x55. This causes
the AMBE-2020™ to enter low power mode. To exit low power mode, the device must be reset through the hardware.
Table 5-A Framed Input : Power Control ID Values Summary
ID Type Description
0x00 Voice Data This ID value instructs AMBE-2020™ to operate in normal fashion
0x55 Low Power Mode
When this mode is activated the AMBE-2020™ Vocoder Chip will go into a mode
which conserves power, where no voice packets are being processed.