DATA SHEET
MAS 35x9F
3.3.5. Ancillary Data
3.3.6. Reading of the Memory Cells “Number of
Bits in Ancillary Data” and “Ancillary Data”
The memory fields D0:FD5...D0:ff1 contain the ancil-
lary data. It is organized in 28 words of 16 bit each.
The last ancillary bit of a frame is placed at bit 0 in
D0:FD5. The position of the first ancillary data bit
received can be located via the content of
When in Broadcast Mode, reading of the cells “Num-
ber of Bits in Ancillary Data” and “Ancillary Data” will
lead to unpredictable results. These cells are
described in Table 3–11 on page 43.
NumberOfAncillaryBits because
The same applies to the “Number of Bits in Ancillary
Data” and “Ancillary Data” of the preliminary data
sheet MAS 3587F.
int[(NumberOfAncillaryBits-1)/16] + 1
of memory words are used.
Example:
First get the content of ‘NumberOfAncillaryBits’
<DW 68 c4 00 00 01 0f d4>
<DW 69 <DR dd dd>
Assume that the MAS 35x9F has received 19 ancillary
data bits. Therefore, it is necessary to read two 16-bit
words:
<DW 68 c4 00
Short Read from D0
00 02 0f d5> read 2 words starting at D0:fd5
<DW 69 <DR dd dd
dd dd>
receive the 2 16-bit words
The first bit received from the MPEG source is at posi-
tion 2 of D0:FD6; the last bit received is at the LSB of
D0:fd5.
Table 3–12: Content of D0:fd5 after reception of 19 ancillary bits.
D0:fd5
MSB 14
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
Ancillary
Data
4th
bit
5th
bit
6th
bit
...
...
...
...
...
...
...
...
...
...
17th
bit
18th
bit
last
bit
Table 3–13: Content of D0:fd6 after reception of 19 ancillary bits.
D0:fd6
MSB 14
13
12
11
10
9
8
7
6
5
4
3
2
1
LSB
Ancillary
Data
x
x
x
x
x
x
x
x
x
x
x
x
x
first
bit
2nd
bit
3rd
bit
Micronas
June 30, 2004; 6251-505-1DS
43
MICRONAS [ MICRONAS ]
