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12
Feature box
DB711 / 710 / 700
Y
U
V
VSA / VSYNC1
HSA / HSYNC1
Feature box DB710
The basic functions of the DB710 are similar in principle to
the DB711. The only visible difference is that the DB710 is
equipped with two field memories, FM1 and FM2. This al-
lows noise reduction and vertical zoom (vertical format
conversion) functions to be implemented.
The upconversion from 50 to 100 Hz in the DB710 is based
on a median interpolation algorithm that reduces both the
field and line flicker. The median filter method uses a 7-
point adaptive median interpolator, whose sampling win-
dow consists of 7 samples, taken in horizontal, vertical and
temporal directions. The 7-point median output will be re-
placed with 3-point vertical median output, if a difference
signal exceeds the externally determined threshold level.
The noise reduction system consists of an adaptive
weighted average post-filter, that is based on the so-called
motion adaptive temporal recursive averaging filter. The
system is used not only for noise reduction, but also to
reduce the cross effects. The noise reduction affects both
the luminance and chrominance components. As men-
tioned above, the noise reduction function requires an ad-
ditional field memory. This field memory, FM2 is identical
to FM1 and it is connected to the IQTV2 circuit in a similar
way.
The characteristics of the vertical format conversion of the
IQTV2 circuit make it possible to always display all vertical
zoom modes with a full vertical resolution of 576 active
lines. This is due to the digital signal processing and linear
vertical interpolation.
FM1
A/D-C
RSTR
3 Mb
12
YUV
ENW
ENR
Y
8
CLK
INIT,CLP
CLK
&
&
27 MHz
13.5 MHz
EEPROM
VCLK
DDC1
interface
SDA
SCL
In DB700 only
Block diagram of the Feature boxes DB711, 710 and 700
SWCK
In DB700 and
FM2
SRCK
DB710 only
3 Mb
RSTW
YUV
RSTR
12
YUV
12
FM2_ENW
FM_RST
IQTV2.1
FM2_ENR
DB711
D0...D11_FM1
UP-C, HFC, HEQ
12
CTI, LTI, Peaking
FM1_ENW
D/A-C
FM1_ENR
2
DB700/710
UP-C, FC, NR, HEQ
CTI, LTI, Peaking,
D/A-C
FM1_RSTW
CLK13.5_I
CLK27_I
OVFL
PWM_REF
DPLL1.02
VSYNC1
HSYNC1
27 MHz
27 MHz
LLC
IIC-bus
Deflection
controller
3
RGB VGA
VGA
to Xtpp
Feature box DB700
The functional features are similar to DB710; median inter-
polation, noise reduction, full vertical resolution etc. In ad-
dition to these features, the DB700 is equipped with a VGA
(video graphics array) interface in order to make it possi-
ble to use the TV set as a monitor for a personal computer.
For this reason, an additional memory circuit is needed.
The memory circuit ic3 is a serial EEPROM, that is pre-pro-
grammed with the data needed for automatic configura-
tion of the display controller in the computer via the dis-
play data channel 1 (DDC1).
The vertical and horizontal sync signals from the VGA con-
nector are fed via inverting schmitt triggers and fed on-
ward to pins 27 (vert sync) and 24/26 (hor sync) of the
DPLL1.
The analog RGB signals are fed through the module with-
out any processing to the RGB video processor ICt1 via the
connector Xtpp on the main board, or via the PIP module,
if installed. If sound signals are also taken from the PC,
they are input via Scart3 + VGA audio module TA710.
The following VGA modes are available:
Resolution
Line frequency
640 x 480
31.5 kHz
640 x 350
31.5 kHz
640 x 400
31.5 kHz
CLK_OPLL
VS_50_100
FM_RST
AY
AU
AV
IIC-bus
CLK
HSYNC_O
VA
VSYNC_O
DSC
VA
HA
EHT, HFB
HD, VD, EW
IIC-bus
IIC-bus
Field frequency
60 Hz
70 Hz
70 Hz
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