Crystal Vision
Card edge operation
DEC105S User Manual R1.1
29
15/12/04
Adjusting signal timing
Use rotary switch (SEL) positions 5, 6, 8 and 9 together with the shaft encoder to change
the following:
•
Output timing relative to the active reference
•
Chroma phase relative to burst (10 bit mode only)
•
Input video timing (10 bit mode only)
The horizontal and vertical timing adjustments relative to the active reference are separate
for 625 and 525 line operation. The settings for composite and Y/C (S-video) phase are
also stored separately, as are the phase settings for PAL and NTSC. This gives a total of
four separate phase adjustments, two each in PAL and NTSC.
All these parameters are automatically maintained when the unit is powered off and
restored when the unit is powered back on.
SEL
Display Text
Description
5
H Pos 0
The shaft encoder adjusts the output video timing relative to the active analogue
timing reference in increments of 37ns. When the maximum adjustment of one
line is reached the value wraps round to zero and the Vpos adjustment is
modified.
6
V Pos 0
The shaft encoder adjusts the output video timing relative to the active analogue
timing reference in increments of whole video lines. When the maximum
adjustment of one frame is reached the value wraps round to zero.
8
Phase 0
(version number
shown in 8 bit mode)
In 10 bit mode chroma phase relative to burst can be adjusted in steps of
approximately 0.1
o
. The display shows the difference from the default setting in
whole degrees.
9
H del +0
(version number
shown in 8 bit mode)
In 10 bit mode the timing of the input video relative to the input syncs can be
adjusted in 37ns steps. The range is -128 to +127, giving approxi/-
4.75 microseconds relative to the factory default timing. The display indicates
the number of adjustment steps used.
Do not leave the SEL switch in position 9 as it is also used as a power-up
factory reset function.
The active output timing reference
The horizontal and vertical timing adjustments operate relative to one of three analogue
timing references. These are an external reference, the composite or Y/C input or an
internal free-running clock. Which of these is the active reference is dependent on the
presence of an external reference or whether an 8 bit or 10 bit mode is in operation.
When an external analogue timing reference is present serial output timing is maintained
relative to the external analogue reference.
