saa5547ps NXP Semiconductors, saa5547ps Datasheet - Page 56

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

Philips Semiconductors
18.6.3
The dynamic scroll region is defined by the MMR Scroll
Area, MMR Scroll Range, MMR Top Scroll line and the
MMR Status. The scroll area is enabled when the SCON
bit is set in MMR Status.
The position of the soft scroll area window is defined using
the Soft Scroll Position (SSP<3:0>), and the height of the
window is defined using the Soft Scroll Height (SSH<3:0>)
both are in MMR Scroll Range. The rows that are scrolled
through the window are defined using the Start Scroll Row
(STS<3:0>) and the Stop Scroll Row (SPS<3:0>) both are
in MMR Scroll Area.
The soft scrolling function is done by modifying the Scroll
Line (SCL<3:0>) in MMR Top Scroll Line. and the first
scroll row value SCR<3:0> in the MMR Status.
2000 Feb 23
handbook, full pagewidth
TV microcontrollers with Closed Captioning (CC)
and On-Screen Display (OSD)
S
OFT SCROLL ACTION
pointer SSP < 3:0 > e.g. 6
soft scroll position
SSH < 3:0 > e.g. 4
soft scroll height
ROW
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Fig.24 Soft scroll area.
56
If the number of rows allocated to the scroll counter is
larger than the defined visible scroll area, this allows parts
of rows at the top and bottom to be displayed during the
scroll function. The registers can be written throughout the
field and the values are updated for display with the next
field sync. Care should be taken that the register pairs are
written to by the software in the same field.
Only a region that contains only single height rows or only
double height rows can be scrolled.
TXT: The display is organised as a fixed size of 25 rows
(0 to 24) of 40 columns (0 to 39), This is the standard size
for teletext transmissions. The control data in row 25 is not
displayed but is used to configure the display page
correctly.
usable for
OSD display
should not be used
for OSD display
should not be used
for OSD display
usable for
OSD display
MBK967
SPS < 3:0 > e.g. 11
STS < 3:0 > e.g. 3
start scroll row
start scroll row
soft scrolling area
Preliminary specification
SAA55xx