SAA5281 Datasheet, PDF (19/48 Pages) NXP Semiconductors – Integrated Video input processor and Teletext decoder IVT1.8

Philips Semiconductors
Integrated Video input processor and
Teletext decoder (IVT1.8*)
Preliminary specification
SAA5281
ENHANCED MODE
In enhanced mode, the number of extension packets captured is reduced to the minimum required for FASTEXT
operation. The first seven chapters can then be used for storage, using the system of pointers. The arrangement of
extension packets is shown in Fig.11.
When in enhanced mode and extension packets are disabled, normal 8-page mode is in operation, but the X/26 engine
is enabled (unlike normal 8-page mode).
handbook, halfpage
ROW
CHAPTER 0 PACKET 24
0
CHAPTER 0 PACKETS 27 / 0 1
CHAPTER 1 PACKET 24
2
CHAPTER 1 PACKETS 27 / 0 3
CHAPTER 2 PACKET 24
4
CHAPTER 2 PACKETS 27 / 0 5
CHAPTER 3 PACKET 24
6
CHAPTER 3 PACKETS 27 / 0 7
CHAPTER 4 PACKET 24
8
CHAPTER 4 PACKETS 27 / 0 9
CHAPTER 5 PACKET 24
10
CHAPTER 5 PACKETS 27 / 0 11
CHAPTER 6 PACKET 24
12
CHAPTER 6 PACKETS 27 / 0 13
not used
14
not used
15
PACKETS 8 / 30 / 0,1
16
PACKETS 8 / 30 / 2,3
17
PACKETS 8 / 30 / 4 to 15
18
not used
19 to 24
MBD788
Fig.11 Organization of the extension memory in enhanced mode.
1996 Nov 04
19