LSI Logic Confidential
Clock and Power Registers
16-7
Copyright © 2001, 2002 by LSI Logic Corporation. All rights reserved.
When Osync is set, the video output PLL is bypassed,
and the video output clock is the Video Input 1 clock.
When Osync is clear and the video out PLL src field is
two, the video output PLL is bypassed and the video
output clock is supplied by the video out clock pin. When
the video out PLL src field is zero or one and Osync is
clear, the video output clock is internally generated with
an operating frequency is determined by N and P as
follows:
VidOutPLL(N) is determined by the table below
.
After reset, N and P are set to 0.
N
[6:4]
See above. This field is reset to 0.
P
[3:2]
See above. This field is reset to 0.
VideoOut
PLL Src
Value
PLL Source
Clock
Application
0
If Osync clear,
Clk pin; else
Video Input 1
Clock pin
Internally generated video
output timing
1
Video Input 1
Clock pin
Video Out locked to video
input stream 1. Both video
input clocks should be the
same. Implementation note:
the video output clock pin
must have minimal skew to the
input clock pin.
2
N/A
Externally generated video
output clock
VideoOutClock
VidOutPLL N
( )
P
1
+
-----------------------------------------
=
N
Output Frequency
0
74.25 MHz
1
74.25/1.001 MHz
2
216 MHz