SAA5X9X Datasheet, PDF (32/68 Pages) NXP Semiconductors – Economy teletext and TV microcontrollers

Philips Semiconductors
Economy teletext and TV microcontrollers
Preliminary specification
SAA5x9x family
8.7 Inventory page
If the TXT0.INV ON bit is a logic 1, memory block 8 is used
as an inventory page.The inventory page consists of two
tables: the Transmitted Page Table (TPT) and the Subtitle
Page Table (SPT).
In each table, every possible combination of the page tens
and units digit, 00H to FFH, is represented by a byte. Each
bit of these bytes corresponds to a magazine number so
each page number, from 100 to 8FF, is represented by a
bit in the table.
The bit for a particular page in the TPT is set when a page
header is received for that page. The bit in the SPT is set
when a page header for the page is received which has the
‘subtitle’ page header control bit (C6) set.
Before the inventory page is enabled the software must
ensure that page request 8 is put on hold.
Bytes in the table
handbook, full pagewidth _column
0
8
row n
n+1
16
24
32
39
n+6
n+7
Bytes in each byte
bit
7
0
7xx 6xx 5xx 4xx 3xx 2xx 1xx 8xx
MGD160
Fig.8 Table organisation.
1997 Jul 07
32