z86131 ZiLOG Semiconductor, z86131 Datasheet - Page 35

• Manufacturer Part Number: z86131
• Description: Ntsc Line 21 Decoder
• Manufacturer: ZiLOG Semiconductor

ZiLOG
D
22) to be used in filtering the XDS data when XDS recovery
has been enabled.
Interrupt Request Register Address = 06h
D
D
ed. This bit clears in each field a few lines after row 15.
D
currently at the end of a field. This bit clears in each field
a few lines after row 15.
D
LOCK signal has changed. The SS register must be read to
determine the current state.
D
channel activity has occurred. The Line 21 Activity register
DS007200-TVX0199
Secondary Filter
All
Time Information
In Band Only
Program Rating
VCR Information
Reserved
Reserved
Reserved
Notes:
Bit
5
0
1
2
3
4
Figure 28. Interrupt Request Register (Address =
ÐD
Ðres.
ÐDLE.
ÐEOF.
ÐdLOK.
ÐdSCH.
1. Setting this register to 00h turns XDS data recovery off.
2. The Time Information Only selection includes the Time of
3. VCR Information selects TOD, LTZ, Net ID, Local Call Let-
4. Program rating filter available on Z86129 only.
dTXT dCAP
R/W
7
Setting bits D
the Classes selected as qualiÞed by the Secondary Filter
(bits D
XDS data are output (even Reserved and UndeÞned).
Day (TOD) and Local Time Zone (LTZ) packets.
ters, Impulse Capture, Tape Delay, Composite 2 and Out
of Band Channel Number packets for recovery.
D
Ðs
Table 22. XDS Secondary Filter Settings
7
Reserved.
0
Active High, indicating that the data line has end-
Active High, indicating that the video signal is
Ðs
R/W
Active High, indicating that the state of the
Active High, indicating that a change in selected
5
ÐD
D
2
.
6
Selects a set of secondary parameters (Table
7
). If Bits D
4
0
dXDS
R/W
D
through D
5
dSCH
R/W
0
D
ÐD
06h)
4
4
4
enables XDS data recovery for
are all set to 1, all Classes of
dLOK
R/W
D
Filter Value (s0:s2)
3
EOF
D
R
2
0h
1h
2h
3h
4h
5h
6h
7h
DLE
D
R
1
P R E L I M I N A R Y
D
res
R
0
must be read in order to determine if the selected data chan-
nel is active.
D
activity has occurred. The Line 21 Activity register must
be read to determine if XDS data is active.
D
activity has occurred. The Line 21 Activity register must
be read to determine if XDS data is active.
D
tion data channel activity has occurred. The Caption Ac-
tivity Register (Address 08h) must be read to determine ex-
actly which caption channels are now active.
D
data channel activity has occurred. The Caption Activity
Register (Address 08h) must be read to determine exactly
which TEXT channels are now active.
Note: Except as noted for the case of D
Interrupt Mask Register Address = 07h
This register identifies which activities in the Interrupt Re-
quest Register are used to cause an interrupt. Setting a bit
to a 1 enables the interrupt when the corresponding event
becomes active. Setting all bits of this register to zero dis-
ables interrupts. Caption Activity Register Address = 08h.
Caption Activity Register Address = 08h
D
nels CC1–T4. Each bit is set High when a mode setting com-
mand for its data channel has been received on Line 21. The
Figure 30. Caption Activity Register (Address = 08h)
Bit
Bit
5
5
6
7
0
Figure 29. Interrupt Mask Register Address = 07h
ÐdXDS.
ÐdXDS.
ÐdCAP.
ÐdTXT.
ÐD
dTXT
R/W
7
D
T4
D
R
ÐActivity Bits.
vice must write a “1” to the appropriate bit in the Inter-
rupt Request Register to clear the Interrupt. Writing a “1”
to any valid bit position the Interrupt Request Register is
equivalent to CLEARing a interrupt request on that bit.
7
7
Active High, indicating that a change in a TEXT
dCAP
Active High, indicating that a change in XDS
Active High, indicating that a change in XDS
Active High, indicating that a change in a cap-
R/W
T3
D
R
D
6
6
dXDS
R/W
T2
D
R
D
5
5
Activity bits for Line 21 data chan-
dSCH
R/W
D
T1
R
D
4
4
dLOK
R/W
CC4
R
D
D
NTSC Line 21 Decoder
3
3
1
and D
EOF
CC3
R/W
D
R
D
2
2
Z86129/130/131
2
, the master de-
R/W
CC2
DLE
D
R
D
1
1
R/W
DAV
CC1
R
D
D
0
0
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