saa5547ps NXP Semiconductors, saa5547ps Datasheet - Page 44

• Manufacturer Part Number: saa5547ps
• Description: Saa550x; Saa554x Tv Microcontrollers With Closed Captioning Cc And On-screen Display Osd
• Manufacturer: NXP Semiconductors

Philips Semiconductors
18.2
The display section has two distinct modes with different
features available in each. The two modes are:
In both of the above modes the character matrix, and
TV lines per row can be defined. There is an option of
9, 10, 13 and 16 TV lines per display row, and a character
matrix (H
combinations of TV lines per row and maximum display
rows give a sensible OSD display, since there is a limited
number of TV scan lines available.
Special Function Register TXT21 and memory mapped
registers are used to control the mode selection.
18.3
All display features are now described in detail for both
TXT and CC modes.
18.3.1
Flashing causes the foreground colour pixel to be
displayed as the background pixels.The flash frequency is
controlled by software setting and resetting the MMR
Status (see Table 28) at the appropriate interval.
CC: This attribute is valid from the time set (see Table 16)
until the end of the row or until otherwise modified.
2000 Feb 23
TXT: This is the display configured for WST with
additional serial and global attributes. The display is
configured as a fixed 25 rows with 40 characters per
row. In the OSD only family this mode can only be
utilised for display of Text style OSD, no Teletext Data
Capture is present.
CC: This is the display configured as the US Closed
Caption mode. The display is configured as a maximum
of 16 rows with a maximum of 48 characters per row.
TV microcontrollers with Closed Captioning (CC)
and On-Screen Display (OSD)
Display modes
Display feature descriptions
F
LASH
V) of 12
9, 12 10, 12
13 or 12
16. Not all
44
TXT: This attribute is set by the control character ‘flash’
(08H) and remains valid until the end of the row or until
reset by the control character ‘steady’ (09H).
18.3.2
CC: This attribute is valid from the time set until end of row
or otherwise modified if set with Serial Mode 0. If set with
Serial Mode 1, then it is set from the next character
onwards.
In Text mode (within CC mode) the background colour is
displayed regardless of the setting of the box attribute bit.
Boxes take effect only during mixed mode, where boxes
are set in this mode the background colour is displayed.
Character locations where boxes are not set show
video/screen colour (depending on the setting in the
MMR Display Control) instead of the background colour.
TXT: Two types of boxes exist, the teletext box and the
OSD box. The teletext box is activated by the ‘start box’
control character (0BH). Two start box characters are
required to begin a teletext box, with the box starting
between the 2 characters. The box ends at the end of the
line or after a ‘end box’ control character.
TXT mode can also use OSD boxes, they are started using
size, implying OSD control characters (BCH, BDH, BEH
and BFH). The box starts after the control character (set
after) and ends either at the end of the row or at the next
size implying OSD character (set at).
The attributes flash, teletext box, conceal, separate
graphics, twist and hold graphics are all reset at the start
of an OSD box, as they are at the start of the row.
OSD boxes are only valid in TV mode which is defined by
TXT5 = 03H and TXT6 = 03H.
B
OXES
Preliminary specification
SAA55xx