Test instructions Display board
GB 55
DVD 950
9.
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.
See the Slave URS how to send a display command.
9.1.6
Key-matrix
Connect a extra 10k( pull-up to pin 36 en 37 of the (P and check
next matrix scanning at these pins.
Figure 9-5
Level A: 5.0V (7%
Level B: 0V (200mV
Check matrix scanning from pin 26 until 33 of the (P.
The results should be the same as the diagram above.
9.1.7
I.R. receiver
Check at pin 23 of the (P if this line switches from low (< 0.3V)
to high (> 4.5V), while pressing a key on a Philips RC5 or RC6
remote control.
9.1.8
Karaoke interface
The karaoke interface (4 lines) is a single direction
communication.
This means that it consists of four uP 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
: 0x70
Command byte
: 0x24
Data byte
: xxxxabcd
Wherea
: a = Karaoke reset.
: b = Karaoke data.
: c = Karaoke clock.
: d = Karaoke strobe.
9.1.9
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 uP 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 uP 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 uP P50 input (uP pin 20): 5V (5%.
3.
Connect the P50 line (connector 1118-5) to ground.
4.
Check again the uP P50 input (uP pin 20): <0V3.
PM3392A
ch1
ch1: low =-46.9mV
ch1: high= 5.09 V
STOP
CH1 2.00 V= MTB10.0ms ch1-
1
B
A
CL 96532065_076.eps
130799