Telephone Interface Daughter Board; Figure 2-8: Audio Board - PictureTel Concorde 4500 Servicing Manual

UNDERSTANDING THE ELECTRONICS MODULE
Keypad
Mic
input 1
Mic
input 2
Audio I/O
2
with I C
interface
Line
IN
Line
OUT
VCR
play/IN
VCR
record/
OUT
Interface
to POTs
daughter card

Telephone Interface Daughter Board

2-16
The following illustration shows a block diagram of the AI board.
Keypad
2
I C
interface
control
and control
Switch
Input
mixer
Switch
VCR
bypass
Switch
Codec;
DTMF;
POTs
control

Figure 2-8: Audio Board

The optional telephone interface daughter board has two parts:
Two-wire and four-wire network connection
Port for attaching an extension telephone or an extension ringer
SIO
Stereo
codec
1610_Data<15..0>
1_Data<31..0>
2_Data<31..0>
MULTIBUS registers;
misc functions;
and DMA control
MULTIBUS buffering,
address decoding; misc
MULTIBUS
Local registers
DSP1610 only
PIO
Bank 0
16k x 16 SRAM
DSP
1610
Bank 1
16k x 16 SRAM
Local registers
C31#1 only
DSP
SRAM
C31
32 K x 32
#1
Local registers
SIO
C31#2 only
DSP
SRAM
C31
32 K x 32
#2
DMA interface
16-b
DMA0
16-b
DMA1