Graphics Daughter Board - PictureTel Concorde 4500 Servicing Manual

UNDERSTANDING THE ELECTRONICS MODULE
Video
Camera
matrix
control
control
Main
camera
8x6
Aux
video
camera A
matrix
Aux
camera B
Composite
doc. cam.
VCR play
Graphics
daughtercard

Graphics Daughter Board

F Y I
2-12
The following illustration shows a block diagram of the VI board.
Send
Luma
video
Y/C
separator
Chroma
decoder
Valid
video
detector
Main pix
Picture
Sub pix
in picture
Color
black
generator
Figure 2-6: Video Board
The Graphics daughter board is attached directly to the Video
board.
When you power on a Concorde¥4500, the Graphics
F.Y.I.
daughter board is assigned to slot 7, even though slot 7 is
physically empty.
DMA bus Multibus
Input
frame
store
Luma
A/D
AVIGA
R-Y
Chroma
B-Y
A/D
DMA bus
Graphics
overlay
frame
store
Output
frame
store
Luma
Far-end
D/A
AVOGA
video
Chroma
D/A
VCR record
Aux monitor
Main monitor