Panasonic KX-TVM200E, Service Manual

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18.3.2. DSP and DPT Block Diagram
McBSP0 sends and receives voice PCM data to and from the PBX interface. The PBX interface has three types of interfaces.
For this reason, each interface has a different device to and from which PCM voice data are sent and received. In any case,
the DSP´s McBSP0 is a clock slave while the clock master varies from interface to interface. In the case of
1 and 3 , the clock
master is the ASIC. In the case of 2 , the clock master is the DPT I/F. The base clock is a 2-MHz PCM serial communication
signal, and voice data of up to 24 channels are sent and received. As for the placements of clock master and clock slave, see
the references at the end of the chapter.
McBSP1 sends and receives the data compressed between the ASIC and the DSP and the data decompressed by the DSP.
The DSP is a clock slave, and the clock master is the ASIC. McBSP1 forms the serial communication that sends and receives
16-bit command data and 16-bit data on the base clock 8 MHz respectively with 24 channels x 2 (mai subframe) = 48
frames.
The HPI-8 is accessed by the CPU and it writes the command setting program data into the DSP.
The CPU has a mechanism at startup to download application programs to each DSP´s internal RAM with the HPI-8. With this
configuration, application programs can be uploaded as necessary after installation.
The DSP unit installed in this system has four channels per unit, and two DSPs are installed.
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KX-TVM200E / KX-TVM200NE