
PSB 7280
Semiconductor Group
147
Data Sheet 1998-07-01
Mailbox Address 06
H
Value after reset: 00
H
(MSB)
(LSB)
d
OPT2
0
S
Re1
Re0
Rd1
Rd0
e
S
Sampling Rate of the codec connected to the JADE, either 8 kHz or
16 kHz. If the sampling rate of the codec is different from the sampling
rate expected by the selected speech coder, the JADE automatically
uses over-/undersampling filters to convert the audio data.
When using G.728 mode and S = 1 indicating a 16-kHz codec is
connected, the postfilter of G.728 is switched off to ensure the
computational power for the over-/undersampling filters is available.
The effect on the audio quality is negligible.
When using G.722 mode and S = 0 indicating an 8-kHz codec is
connected, the bandwidth of the G.722 input/output data is reduced to
3.4 kHz. Nevertheless, the compressed data stream is fully compatible
and interoperable with the G.722 standard.
0
Codec has 8 kHz sampling rate
1
Codec has 16 kHz sampling rate
Restricted number of bits for encode and decode. Only used for G.722,
that offers modes where less than 8 bits per byte are used: 7 bits per
byte (56 kbit/s) and 6 bits per byte (48 kbit/s).
00
8 valid bits per byte
01
7 valid bits per byte
10
6 valid bits per byte
11
Reserved
Rd is the same as the above, but indicates the mode of the data in this
packet.
Encoding mute enable. After switching, a ramping function is
implemented to avoid audible clicks.
0
Encoding Mute disabled
1
Encoding Mute enabled
Re(1-0),
Rd(1-0)
e