Philips 26FW5220, Service Manual

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SCL. This is the clock wire of the two-wire single master bi-directional I2C bus.
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SDA. This is the data wire of the two-wire single master bi-directional I2C bus.
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STANDBY. The Hercules generates this signal. This can enable the power supply
in normal operation and disable it during Standby. It is of logic “high” (3.3 V) under
normal operation and “low” (0 V) during Standby.
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IR. This input pin is connected to an RC5 remote control receiver.
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SEL-IF. This is an output pin to switch the Video SAW filter between M system and
other systems.
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0: NTSC M (default)
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1: PAL B/G, DK, I, L
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NVM_WP. The global protection line is used to enable and disable write protection
to the NVM. When write to the NVM is required, pin 7 of the NVM must be pulled to
logic '0' first (via Write_Protect of the micro-controller pin) before a write is
performed. Otherwise pin 7 of NVM must always be at logic “1”
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0: Disabled
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1: Enabled (default)
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SOUND_ENABLE. This pin is use to MUTE the audio amplifier. It is configured as
push pull.
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STATUS_1. This signal is used to read the status of the SCART 1 input.
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STATUS_2. This signal is used to read the status of the SCART 2 input.
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HERC_RESET. This pin is use to switch the +1.8V supply.
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POWER_DOWN. The power supply generates this signal. Logic “high” (3.3 V)
under normal operation of the TV and goes “low” (0 V) when the Mains input
voltage supply goes below 70 V_ac.
122 P2.4/ PWM3 STANDBY P2.4
123 P2.5/ PWM4 (for future use) -
126 P1.2/ INT2 (for future use) -
127 P1.4/ RX HERC_RESET -
128 P1.5/ TX POWER_DOWN P1.5
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Keyboard. Following are the Keyboard functions and the step values (8 bit) for it.
Table: Local keyboard values
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TV_IRQ. This signal is the interrupt from the Scaler IC.
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TV_SC_COM. This signal is used for the communication with the Scaler IC.
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EXT_MUTE. This signal is used to reduce the Switch-off plop.