Chapter 4; Basic Upc Requirements; Control Circuitry - Mitsubishi Electric WS-48513 Troubleshooting Manual

As in the two earlier integrated HDTV chassis, V19
and V21, the V23 uses two Microprocessors in the

Control circuitry.

1) TV µPC ... controlling the analog circuitry.
2) DM µPC ... controlling the digital circuitry.
The two µPCs constantly communicate with each other.
User commands are input to the TV µPC. Digital com-
mands are forwarded from the TV µPC to the DM µPC.
The TV µPC generates Control commands from two
sources.:
1) User commands from the front panel or remote
control
2) Commands from the DM µPC.

Chapter 4

Control Circuitry
4-1
Even though circuitry is becoming more complex, the
same basic requirements must be met for a µPC to op-
erate.
Basic µPC Requirements
Figure 4-1 illustrates the four basic requirements for
the TV µPC operation in the V23.
1) DC Supply ... 3.3V-ES and 5VS.
2) Ground Returns ... pins 8, 9 and 14.
3) Timing Signal ... 15 mHz Clock Oscillator
4) Reset circuitry ... sets the µPC to its nominal
starting point
There is similar circuitry for the DM µPC. Since the
DM Module is considered a replaceable component