
PSB 7230
Firmware Features
Semiconductor Group
134
Data Sheet 1998-07-01
The communication between user and JADE AN starts in the neutral mode. To initiate
transfer of speech data, the user sends a command data structure set to the desired
compression mode(s) in a neutral size packet. The mode change affects the JADE’s
input pipeline stage in the next 10 ms period. This means that if the decode mode
changes, the next packet from the user will change in size (corresponding to the new
decode mode), while if the encode mode changes, the third packet from the JADE AN
will be affected (packets from the JADE AN represent the output stage of the pipeline).
As a general rule, any changes to the current operating mode or options (volume, mute,
etc.) transferred to the JADE AN from the user take effect on the input captured on the
next 10 ms boundary.
To change compression modes, the user must first send four neutral mode command
packets. The first neutral mode command will be in a full-size packet per the current
operating mode, while the following neutral mode command packet does only contain
the 8 words header. Two neutral packets are required to clear the JADE’s pipeline.
During that time the JADE AN will reorganize its memory (if required) and re-initialize
internal variables.
Note: When a mode change is requested by the user without sending four neutral
packets before, the JADE AN may not work stable.
Commands
The following section defines the commands which are sent from the user to the JADE
AN. Any changes in mode affects the input pipeline stage in the next 10 ms time slot.
1. Command header word
2. Checksum
The sum of the six following words (regarded as signed 16 bit values) in the command
header. If the checksum is wrong, no modes or options are changed, and an error status
is sent back in the next status header.
1)
The 8-kHz pass-through mode is not available when Host/Host is selected as interface combination for
compressed/uncompressed data.
Table 22
Mode
Neutral
G.723
G.711
8 kHz pass-through
1)
Compressed Words (Bytes)
0 (0)
4 (8)
40 (80)
80 (160)
0
0
0
0
1
0
0
0
0
0
0
0
1
1
1
1