Mitsubishi Electronics WS-55513, WS-65513, WS-48613, WS-48513 manual Input Command Circuitry

Both the µPCs have the ability to reset each other if communication is lost. IC7C30 serves as a Reset inter- face between the two µPCs and the front panel Reset button. If the TV µPC gets no response from the DM, it outputs a High at pin 73 of IC7A00. The High is routed through IC7C30 and drives the DM-RESET in- put at pin 15 of the TC connector High.

Conversely, if the DM µPC gets no response from IC7A00, the DM outputs a Low at pin 18 of the VC connector. The Low, through IC7C30 activates a TV Reset pulse from IC7C70.

When the front panel recessed Reset button is pressed, both µPCs are reset through IC7C30.

IC7A00 also outputs reset pulses for the Convergence Generator, Audio Control, 3DYC and MLink circuitry.

Input Command Circuitry

Figure 4-3illustrates the Command Input circuit. It is basically the same as that in the V19 and V21 so an in depth description is only necessary on those parts that are different.

The front panel Buttons are in a conventional resistive ladder configuration. Pressing a button changes the voltage at the KSC0 or KSC1 input of the µPC. The command is identified by the change in voltage at the KSC input.

There are differences in the Remote input circuitry due to the Remote Learning feature of the V23. As in pre- vious models there are two Remote Preamps:

1)A conventional Mitsubishi Preamp.

2)A wideband Preamp amplifying the IR signals of most manufacturers.

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