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GB 32
5.
DVD612 /XX1
5.8.4
Reset
Check next reset timing with an oscilloscope at pin 10 of the
microprocessor.
PM3392A
ch2
ch1
T
2
1
CH1 2.00 V=
CH2
2 V=
BWL MTB 100ms- 1.04dv ch2+
Figure 5-42
Timing: 400msec < T1 > 700msec.
CH1: +5Vstby voltage at power on.
CH2: Voltage at pin 10.
5.8.5
Display steering
Check next timing and level for all grid-lines (G1 r G14).
PM3392A
ch1:
low =-34.2 V
ch1
ch1:
high= 3.98 V
1
T
CH1 10.0 V=
Figure 5-43
1. Check level A: +4V5 +/-10% for grid lines 1 => 11
2. Check level A: +4V0 +/-10% for grid lines 12 => 14
3. Check level B: -33V +/-10%
4. Check timing and levels of segment-lines P1 => P10:
PM3392A
ch1
1
T
CH1 10.0 V=
BWL MTB 500us- 1.04dv ch1+
Figure 5-44
Level A:+4V5 +/-10%
Level B:-33V +/-10%
The data on these segment lines depend on the characters
that are displayed.
The characters can be set by sending I2C commands to the
display.
Diagnostic software descriptions and troubleshooting
T1
CL 96532065_073.eps
130799
A
B
STOP
MTB 200us
2324us ch1+
CL 96532065_074.eps
130799
A
B
CL 96532065_075.eps
130799
www.rtv-horvat-dj.hr
See the Slave URS how to send a display command.
5.8.6
Key-matrix
Connect a extra 10kΩ pull-up to pin 36 en 37 of the µP and
check next matrix scanning at these pins.
PM3392A
ch1:
low =-46.9mV
ch1
ch1:
high= 5.09 V
B
1
CH1 2.00 V=
MTB10.0ms
Figure 5-45
Level A: 5.0V +/-7%
Level B: 0V +/-200mV
Check matrix scanning from pin 26 until 33 of the µP.
The results should be the same as the diagram above.
5.8.7
I.R. receiver
Check at pin 23 of the µP if this line switches from low (<
0.3V) to high (> 4.5V), while pressing a key on a Philips RC5
or RC6 remote control.
5.8.8
Karaoke interface
The karaoke interface (4 lines) is a single direction
communication.
This means that it consists of four µP output lines.
The interface can be checked by setting or resetting these
output-ports via the I2C bus.
Send next command via the I2C bus:
Address
Command byte
Data byte
Where
5.8.9
P50 interface
P50 is a bi-directional serial interface, which is used for
communication between video equipment. For European
sets, this communication goes via pin 10 of the scart-bus. In
other regions, it can be a cinch bus at the back of the set.
1. Keep the µP in reset by short-circuiting emitter and
collector of transistor 7108, via resistor 3100 and 3104
transistor 7101 is switched on.
2. Check the voltage at the P50 output connector 1118-5: <
200mV.
When the reset is released the µP output-pin becomes low
and transistor 7101 is switched off.
1. Check the voltage at the P50 output connector 1118-5:
4V9 +/-5%.
2. Check also the µP P50 input (µP pin 20): 5V +/-5%.
3. Connect the P50 line (connector 1118-5) to ground.
4. Check again the µP P50 input (µP pin 20): <0V3.
A
STOP
ch1-
CL 96532065_076.eps
130799
: 0x70
: 0x24
: xxxxabcd
: a = Karaoke reset.
: b = Karaoke data.
: c = Karaoke clock.
: d = Karaoke strobe.
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