PCA8514T PHILIPS [NXP Semiconductors], PCA8514T Datasheet - Page 36

• Manufacturer Part Number: PCA8514T
• Description: Stand-alone OSD
• Manufacturer: PHILIPS [NXP Semiconductors]

Philips Semiconductors
Table 42 Selection of the character size for the first line
10 MISCELLANEOUS
10.1
Figures 30 to 34 show the Space Code and Carriage
Return Code in the 4 different Background/Shadowing
modes:
1995 Nov 27
FS1 FS0
Mode 0: the No background mode. Both the Space
Code and the Carriage Return Code are displayed as
transparent (no bit) patterns with the video signal as the
background. This is shown in Fig.30.
Mode 1: the North-West shadowing mode. Both codes
are displayed in the same manner as for Mode 0. This is
shown in Fig.31.
Mode 2: the Box shadowing mode. The Space Code is
displayed as an opaque pattern with a selected
background colour. This will also be the background
colour of the character following the Space Code. The
Carriage Return Code however, is displayed as a
transparent (no bit) pattern superimposed on the video
signal. This is shown in Fig.32.
The Space Code can also be displayed as a transparent
pattern on the video signal, and this is shown in Fig.33.
The choice of whether the Space Code displays an
opaque pattern or a transparent pattern is mask
programmable.
Mode 3: the Frame shadowing mode. The Space Code
and Carriage Return Code are displayed as transparent
patterns with background colour. This is shown in
Fig.34.
Stand-alone OSD
0
0
1
1
Space and Carriage Return Codes in different
Background/Shadowing modes
0
1
0
1
1H/1V (the default size)
2H/2V
3H/3V
4H/4V
CHARACTER DOT SIZE
36
10.2
Two (or more) character font cells may be combined in a
horizontal or vertical direction to create a new higher
resolution pattern.
The combination of two cells in a horizontal direction is
straight forward and requires no special precautions to be
taken. When combining character cells in this manner all
4 Background/Shadowing modes are available. An
example of combining two character font cells in a
horizontal direction is shown in Fig.35.
However, the combination of two character font cells in a
vertical direction is more difficult and care must be taken;
otherwise, the new pattern may be created with gaps in its
shadowing. An example of a character pattern with gaps is
shown in Fig.37. Providing the steps listed below are
followed no problems with shadowing will occur.
The line spacing between two rows of characters must
be programmed to 0H. This procedure is explained in
Section 9.3.2.
If the North-West shadowing mode is selected then
when combining two character cells in a vertical
direction Row 0 must contain the same bit pattern as
held in Row 18 of the character directly above it. This is
shown in Fig.38.
If North-West shadowing is not required then Row 0
should contain all zeros.
Combination of character font cells
Product specification
PCA8514