SAA5X9X Datasheet, PDF (34/68 Pages) NXP Semiconductors – Economy teletext and TV microcontrollers

Philips Semiconductors
Economy teletext and TV microcontrollers
Preliminary specification
SAA5x9x family
8.8 Memory Organisation of SAA5290, SAA5291, SAA5291A and SAA5491
Teletext packets each contain 40 bytes of data and one packet is stored in each row of the text memory, the row used
being dependent on the packet number.
Packet 0, the page header, is split into 2 parts when it is written into the text memory. The first 8 bytes of the header
contain control and addressing information. They are Hamming decoded and written into columns 0 to 7 of row 25.
handbook, full pagewidth
Basic Page Block
0
6 78
Row 0 OSD only
aw/ag
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Control Data
0
9
Extension Packet Memory
Row 0
1
2
Packet X/0
Packet X/1
Packet X/2
Packet X/3
Packet X/4
Packet X/5
Packet X/6
Packet X/7
Packet X/8
Packet X/9
Packet X/10
Packet X/11
Packet X/12
Packet X/13
Packet X/14
Packet X/15
Packet X/16
Packet X/17
Packet X/18
Packet X/19
Packet X/20
Packet X/21
Packet X/22
Packet X/23
Packet X/24⁽¹⁾
VPS Data
23
Packet X/24⁽²⁾
Packet X/27/0
Packet 8/30
39
MGK467
(1) If X24 Position bit = 1.
(2) If X24 Position bit = 0.
Fig.10 Packet storage locations.
1997 Jul 07
34