z86230 ZiLOG Semiconductor, z86230 Datasheet - Page 37

• Manufacturer Part Number: z86230
• Description: Advanced Violence Blocking And Ntsc Line 21 Xds
• Manufacturer: ZiLOG Semiconductor

PS000400-TVC0499
XDS D
The XDS filters on the Z86230 greatly reduce the amount of Field 2 data passed
on to the master device for further processing and interpretation; however, the
master device must still interpret the filtered data stream in accordance with EIA-
608A. In other words, only the selected XDS data Class and Type packets are cho-
sen. The filtered data stream contains all of the XDS command and data packets.
Though the Z86230 filtered data stream is in full compliance with the EIA-608
specification, the master device must still interpret the necessary packets to ensure
full compliance with EIA-608A.
N
all other Z86230 predefined XDS filters. This change has been made to minimize the
amount of data passed through the Program Rating XDS filter, thereby minimizing the
interpretation and communications load on the master device. When the XDS Filter Regis-
ter is set to 61h (Class=01h (Current), Type=05h (Program Rating) the only data from
Line 21
OTE
1. Program Rating Packet: [
2. The
:
ATA
The Z86230 XDS filter for Program Rating information functions differently than
data byte pair as defined in EIA-608. The program’s rating is encoded per
EIA-608 in the
computed per EIA-608A. The checksum calculation includes the
packet [
ter.
Field 2
R
ECOVERY
END
01h,05h
that passes through the filter is:
Z86230—PRELIMINARY
Packet [
xxh
] even though this value was not passed through the fil-
0Fh
byte pair.
,
CHKSUM
xxh,xxh
]. A 2-byte packet that includes a
]. The Current Class Program Rating
C
ONTROL
R
CHKSUM
START
EGISTERS
37