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EN 124
9.
EM5A P/M
This RGB output of the board is signaled into the set (HOP-
section of SSB [B4].)
9.6.2
Matrix
The YPbPr-signal format is converted to RGB via the matrix
function. In 480p-format, the PAL matrix is used, otherwise the
ATSC matrix is used.
The matrix choice is made with TDA8601 (SW1, 7107.)
This switch is controlled via the command IO-1 (called MATRIX
SELECT in the figure.)
9.6.3
Sync Slicer
The sync slicer extracts the horizontal and vertical
synchronization signals for the HOP (in the set):
•
From the 3-level sync pulses Y of the 1080i YPbPr
•
From the 3-level sync pulses Green of the 1080i RGB
•
From the normal sync pulses of the 480p signal
Explanation of 3-level sync shown in picture:
+ 350
+ 300
0
P'
,P'
B
R
- 300
- 350
+ 700
+ 300
Y',R',G',B'
0
- 300
0
H
Figure 9-12 3-level sync signal
Example of a 2-level sync pulse: CVBS-signal with two levels
of sync (-300 mV, 0 mV)
Example of a 3-level sync pulse: ATSC-signal with three levels
of sync (-300 mV, 0 mV, +300 mV)
The amplitudes of the Y, R, G, B signals are 700mV;
amplitudes of the Pb and Pr signals are 350mV.
9.6.4
Sync Selection
If the synchronization is derived from Y or Green, the H and V
sync from the sync-slicer must be selected.
•
When YPbPr-signal or RGB-signal is 480p-format: sync
signals will be V-770 and H-770-2 sync.
•
When YPbPr-signal or RGB-signal is 1080i-format: sync
signals will be V-770 and H-770-3 sync.
When the sync is separate (H and V), the sync of the source
must be selected.
The IO-4, IO-5 control-lines select the sync-inputs of the
HEF4052 (7102.)
In our figure, these control-lines are named SYNC SELECT 2
and SYNC SELECT 1.
Via IO-6 line (called TRISTATE SYNC), the sync output can be
put in tri-state.
Control Function
The different selections are made by the I/O expander,
2
controlled by I
C.
These selections can be made with the user interface.
Circuit Descriptions and Abbreviation List
9.7
9.7.1
9.7.2
9.7.3
CL 16532043_022.eps
080501
Audio
Audio left and audio right are connected via the two cinches
and passed through the module.
Video: High-end Input Processor (HIP,
Diagram B2)
In the EM5A, the HIP TDA932xH is used, which contains the
following functions:
•
IF demodulation.
•
Group delay correction.
•
AFC signal generation, used to track drifting transmitters.
•
Sound carrier re-generation (SIF).
•
AM demodulation.
•
Sync acquisition, delivering H
•
Switching off IF-filtering.
Inputs
The HIP has various inputs:
•
Full matrix switch with:
–
Two CVBS inputs.
–
Two Y/C (or additional CVBS) inputs.
–
One CVBS front-end input.
•
Two RGB inputs.
Outputs
One can select three, separate switchable, outputs:
•
One YUV-output, which is fed to the PICNIC.
•
Two CVBS outputs).
Video Processing
The sandcastle-pulse, created by the HIP, is not used for
synchronisation (only for the Comb filter). The HOP will
generate synchronisation signals derived from the feature box
(PICNIC, pin 60 and 61) signals.
If a VCR is connected, there is also an automatic correction for
MacroVision (r). This is active for the external sources and the
pre-sets 0, 90-99.
The HIP itself (no external voltage) controls the Y/C switch in
the HIP.
The chrominance decoder in the HIP is full multi-standard:
PAL/SECAM/NTSC.
Different crystals can be connected to the pins 54 to 57 without
any alignment. The crystals are also used as a reference for the
synchronisation. A digital control circuit that is locked to the
reference signal of the colour decoder determines the start-up
of the sync.
Note: You may only replace these crystals by the original ones.
If just a crystal is taken, the internal capacitance will be different
and the effect will be that there is no colour.
In the HIP a sync separation circuit is integrated; the HIP
delivers the H
and V
to the PICNIC.
A50
A50
and V
.
A,
A
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