SDA9400 Datasheet, PDF (21/94 Pages) Micronas – Scan Rate Converter using Embedded DRAM Technology Units

SDA 9400
The three different “multi picture modes” can be selected by the parameter MULTIPIC. MULTIPIC=0
defines normal operation without compression. The table below explains the performed
compressions depending on the “multi picture mode” and the corresponding aspect ratio of the
display.
Input write parameter: MULTIPIC
MULTIPIC (1Bh)
00 (Multi Picture Off)
01 (fourfold)
10 (twelvefold)
11 (sixteenfold)
Horizontal compression
Vertical compression Aspect ratio of the display
normal operation, no compression
2:1
4:1
4:1
2:1
3:1
4:1
4:3
16 : 9
4:3
To get a “multi picture display” the following executions must be performed:
Entering a “multi picture mode” is defined by transmitting a value MULTIPIC>0. This value of
MULTIPIC must not be equal to the previous value of MULTIPIC. During the following two fields the
memory will be completely filled with a constant colour defined by the parameters YBORDER,
UBORDER, VBORDER. This colour is identical to the background and the borders of the multi
picture display. The same procedure is performed when the “multi picture mode” changes from a
value MULTIPIC>0 to another value MULTIPIC>0. Beginning with the following field the
compressed input picture is written at the position PICPOS addressed via I²C-bus. The user has to
address all possible positions PICPOS one after the other to build a complete multi picture display.
In sequence, the background colour is replaced by the small pictures. The not overwritten areas of
the background colour form the borders of the multi picture display.
The pictures can be taken from the same source (’Shots of a Sequence’) or from different sources
(’Tuner Scanning’). The actual addressed picture is moving until “Freeze mode” is activated.
Before entering “multi picture mode” the “H-and-V-freerunning mode” (see also Output sync
controller (OSC) on page 40) should be activated via the I²C bus bits HOUTFR and VOUTFR,
especially when “Tuner Scanning” will be performed. The “H-and-V-freerunning mode” avoids
synchronization problems of the display during changing the tuner channel.
The values of ALPFIP (Active Lines Per Field Input, see also Input sync controller (ISC) on page
11), and ALPFOP (Active Lines Per Field Output, see also Output sync controller (OSC) on page
40) must be set to 144 or 121, respectively. Only these standard signals corresponding to PAL and
NTSC systems are supported. A mixture of PAL and NTSC signals is also possible.
Input write parameter
Parameter
MULTIPIC
PICPOS
YBORDER
UBORDER
Subaddress
1Bh
1Bh
17h
18h
Description
Defines the multi picture modes
Position of the picture in the multi picture mode (only
valid for MULTIPIC>0)
Y background value
U background value
Micronas
21
Preliminary Data Sheet