Lan Block - Panasonic BB-HCM511A Service Manual

BB-HCM511A/BB-HCM531A
a register setting from the host, amplification, AD conversion and gain adjustment are performed.
The sampling frequency of the A/D conversion is 8kHz and it is converted to the PCM in the format of 8bit and µ law. Then,
64kbps data are output to the IC102 on the CPU board through the Serial I/F.
The data transfer of the Serial I/F is BCLK (256 kHz).
4. The data compression of 32kbps is performed in the ADPCM Block inside of the IC102 and the data transferred as audio data.
[Speaker audio]
1. The ADPCM audio data are sent from the PC and, after data decompression in the ADPCM block of the ASIC (101), the data
are transferred as the audio data of 64kbps to the PCM Codec (IC501) through the Serial I/F.
2. After the µ law to linear conversion, amplification and DA conversion, they are output to pin 2 of the speaker jack (CN504) as
audio output signal in the PCM Codec (IC501).
4.5.

LAN Block

Composed of ETHERNET MAC Block inside of the IC102 and the IC105 (ETHER-PHY) on the CPU board, and the T501
(Transformer) and the CN601 (RJ45 jack) on the PoE Board.
The T605 (Transformer) obtains isolation between the Set and the Ethernet.
ETHERNET MAC and the IC105 (ETHER-PHY) are connected by a signal called MIIBus and it makes Ether net data sending
and receiving possible.
Sending
The communication data sent from the IC102 is converted to Ethernet signal (100Base-Tx, 10Base-T) at the IC105 and sent
from the CN601 through the T601.
Receiving
The Ethernet signal received from the CN601 is converted to the communication data at the IC105 and received to the IC102.
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