2002 May 06
76
Philips Semiconductors
Objective specification
Enhanced TV microcontrollers with
On-Screen Display (OSD)
SAA567x; SAA569x
23.5.12 F
RINGING
A fringe (shadow) can be defined around characters. The
fringe direction is individually selectable in any of the
North, South, East and West directions using the MMR
Fringing Control.
The colour of the fringe can also be defined as one of the
entries in the CLUT, again using MMR Fringing Control.
An example of fringing is shown in Fig.32.
CC:
The fringe attribute (see Table 35, bit 9) is valid from
the time set until the end of a row of a display window, or
otherwise modified.
TXT:
Bit TXT4.SHADOW ENABLE controls the display of
fringing in single page mode and in double Page A.
Bit TXT26.SHADOW ENABLE B controls the display of
fringing for Page B in double window mode.
Whenset,allthealphanumericcharactersbeingdisplayed
are shadowed, graphics characters are not shadowed.
handbook, full pagewidth
MBK972
Fig.32 South and south-west fringing.
23.5.13 M
ESHING
This attribute affects the background colour being
displayed. Alternate pixels are displayed as the
background colour or video. The structure is offset by one
pixel from scan line to scan line, thus achieving a checker
board display of the background colour and video.
An example of meshing and meshing/fringing is shown in
Fig.33.
CC:
The setting of the MSH-bit in MMR Display Control
has the effect of meshing any background colour.
TXT:
There are two meshing attributes. One only affects
black background colours TXT4.B MESH ENABLE in
single window mode or in double window mode for
Page A, and TXT26.B MESH ENABLE B for Page B.
A second only affects backgrounds other than black
TXT4.C MESH ENABLE in single window mode or in
double window mode for Page A, and
TXT26.C MESH ENABLE B for Page B. A black
background is defined as CLUT entry 8, a non-black
background is defined as CLUT entry 9 to 15.