
PSB 7238
Firmware Features
Semiconductor Group
145
Data Sheet 1998-07-01
Note: Independently of the interface selection for the compressed audio, always the
most significant bit of the most significant byte is transferred first, e.g. when using
pass-through modes, the 16-bit samples are split up into two bytes and the most
significant bit of the most significant byte is transferred first (big endian).
6.2.1.3
The following paragraph describes an H.221/H.223 oriented protocol which transfers the
control information inband with the compressed audio data.
The user sends commands and data, and the provider sends status and data.
Commands and data or status and data are grouped into blocks of 16-bit words.
Between the user and the JADE one data packet is transferred each way every 10 ms.
The packet, that is transferred from the video processor to the JADE - called “command
data” - consists of eight command words followed by the appropriate number of data
words for the current speech algorithm:
Compressed Audio Protocol with Inband Control
G.723 Mode
Supported in ITU-T
C-Code Version:
4.1, 5.0, 5.1
Bit (1-0) of first
Byte
00
Comment
G.723, 6.3 Kbit/s
6.3 Kbit/s Mode
standard packet
5.3 Kbit/s Mode
standard packet
Silence packet with
filter coefficients,
same for 6.3 and
5.3 Kbit/s mode
Silence packet
without any data,
same for 6.3 and
5.3 Kbit/s mode
G.723, 5.3 Kbit/s
4.1, 5.0, 5.1
01
G.723, Silence
Insertion Descriptor
(SID) packets
5.0, 5.1
10
G.723,
untransmitted
packets
5.0, 5.1
11