Service manual WP 895/895F, CP885/885F, CP485F
5-4-3 - Controller I/O pin configuration and function
There exist different kinds of ports. The universal ports serve as digital I/O and have additional special input and output
functions. A subset of the universal ports serves as input for the analogue-to-digital converter.
- Controller I/O pin configuration and function table
configuration
Stand byTV ONpinnamedescription
1PowerPush Pull LowPush Pull HighSwitch OFF / ON SMPS
2AG CHigh impedanceHigh impedanceTuner AGC level input -
For factory use only
5Mod SWHigh impedancePush PullHigh = Negative
modulation, Low = Positive
modulation (L/L?).
6SECAM L?High impedancePush PullLow = L, High =L?
7AFCHigh impedanceHigh impedanceADC input
8IRHigh impedanceHigh impedanceInterrupt input
9SC1 SWHigh impedanceHigh impedanceSCART 1 slow switching -
ADC input
10SC2 SWHigh impedanceHigh impedanceSCART 2 slow switching -
ADC input
61MutePush PullPush PullHigh = Mute active
62LEDOpen DrainOpen Drain
63K BHigh impedanceHigh impedanceKeyboard input - ADC
input
64OCPHigh impedanceHigh impedanceOver Current Protection -
Switch the set to Std by if < 2.
To reduce power consumption in stand by mode all ports not used are configured in high impedance mode.
5-4-4 Tuning
The AFC information is supplied by the demodulator IC, and becomes available on VCT pin 7 for controlling software.
The controlling software uses this information for tuner frequency tracking ( automatic following ). The AFC window
is typically between 50 KHz and 100 KHz.
The minimum frequency step of the tuner is 50 Khz.
This AFC function is disabled when a program is tuned using the direct frequency entry or after fine tuning adjustment.
Therefore it is recommended to tune channel with the TV search function ( manual or ATSS ) or using the direct
channel entry to enable the Automatic Frequency Control.
5-4-5 Automatic Format switching and W SS
W hen AUTO mode is selected by the user, the television will automatically select a mode for the user. The form at
information is suppliedby SCART pin 8 level when in AV mode or by WSS data. The signal contains codes as defined in
the WSS European Telecommunication Standard, ETS 300 294. Briefly, the signal is received at the beginning of line
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ACEC
