Crystal Vision
Statesman
DEC105S User Manual R1.1
14
15/12/04
Timing adjustment
The position adjustment tab provides access to the following:
•
Horizontal position - output timing in 37ns steps
•
Vertical position - output timing in one line steps
•
Horizontal delay - input timing in 37ns steps (10 bit mode only)
Position adjustment controls
Different horizontal and vertical timing adjustments can be maintained for 625 and 525
line operation. However, the horizontal delay is common to both 525 and 625
Note:
The horizontal delay and phase controls are not available in 8 bit mode.
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.
When no external analogue timing reference is present the serial output timing depends
on whether the decoder is in 10 or 8 bit mode. In 10 bit mode the serial output is timed to
the composite or Y/C input. In 8 bit mode the output is timed to a free running factory set
clock. The following tables summarises the possible output timing reference sources:
Active timing reference
Ext. Ref.
Mode
External analogue input
Present
10 or 8 bit
Composite or Y/C input
Not present
10 bit
Free running internal clock
Not present
8 bit
