AT2004 Datasheet, PDF (13/25 Pages) List of Unclassifed Manufacturers – 4 Channels ADPCM Processor with Echo Cancellation and Conferencing

AT2004
4 Channels ADPCM Processor with Echo Cancellation and Conferencing
Command Byte[7:0]
Description
0 0 1 0 0 0 A1 A0 Conferencing Header & Chip ID
Channel Configuration Begin
To begin on first channel, set to 0
Ch0 Gain Conf. Mode
Chan #1
Conferencing command for channel 0
Chan #2
Chan #3
Ch1 Gain Conf. Mode
Chan #1
Conferencing command for channel 1
Chan #2
Chan #3
Ch2 Gain Conf. Mode
Chan #1
Conferencing command for channel 2
Chan #2
Chan #3
Ch3 Gain Conf. Mode
Chan #1
Conferencing command for channel 3
Chan #2
Chan #3
Note: Chan #1, Chan #2 and Chan #3 are channel number of conferencing resource with current channel. The format of data fields gain
and conf. mode are specified below.
The Gain of the channel is set according to the following table:
Gain[1:0] Description
0 0 Gain = 0dB
0 1 Gain = +6dB
1 0 Gain = -12dB
1 1 Gain = -6dB
Default: gain is set to 0dB.
The Conf. mode of the channel is set according to the following table:
Conf. mode[1:0]
0
0
0
1
1
0
1
1
Description
Disable conferencing
One channel (specified by Chan #1) is used for conferencing
Two channels (specified by Chan #1, Chan #2 ) is used for conferencing
Three channels (specified by Chan #1, Chan #2, Chan #3) is used for
conferencing
Chip Power-up Power-down command
The chip power-up / power-down command is a single command byte which enables and disables the AT2004 chip.
Power-up chip mode will:
1. Stop the sample processing
2. Power-up the PLL to the specified multiplier frequency
3. Reset algorithms on the chip.
Power-down chip mode will:
1. Stop the sample processing.
2. Switch the system clock to the power down clock running approximately at 125 Hz.
0 0 0 1 0 0 A1 A0 Power-up Chip Command
0 0 0 0 1 0 A1 A0 Power-down Chip Command
Note: A1, A0 refers to the chip ID.
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©2001 Atelic System, Inc