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When the results of check item (3-16.4.) are "30"
(Detection of HPD is OK / Detection of RXSENSE is OK )
Checking the EDID register. (HDMI OUT1)
Check item(3-16.5.).
Check the Monitor EDID :
① Unplug the AC cord. Plug the AC cord into a power outlet.
② Send the transmission command "m_1" from Termite.exe.
Are the first eight bytes of the returned value "00FFFFFFFFFFFF00"?
YES
3.3V
TMDS Signal
TMDS
Example of waveform in check ① Example of waveform in check ②
Voltage scale : 1.0V/div
Voltage scale : 1.0V/div
Time scale : 20ms/div
Time scale : 1s/div
Check item(3-16.6.).
Checking the TMDS :
Check the TMDS waveform at the following test
point.
N3402
HDMI OUT
[MONITOR1]
YES
NO
Check for a short circuit in the TMDS line.
If there is no problem, the HDMI Tx
[N3402] is faulty.
Replace with a new device.
HDMI Tx [N3402] is faulty.
Replace with a new device.
Recheck from
check item (3.4.)
If it does not work, replace the PCB.
NO
less than 100KHz
NO
5V
5V
This diagram shows an example of the DDC communica-
tion waveform.
-The high level voltage is 5V.
-The frequency of the DDC CLK is 100kHz or less.
Check at each test point.
Voltage scale : 2.0V/div
Time scale : 40us/div
Check item(3-16.7.).
Check the communication :
Are the waveforms for "CKL" and "DATA" at the
test point near the HDMI output connector
[N3402] correct (as shown in the figure)?
N3402
HDMI OUT
[MONITOR1]
DDCSCK
DDCSDA
YES
NO
Check for a short circuit in the DDC line.
If there is no problem, the HDMI Tx
[N3402] is faulty.
Replace with a new device.
HDMI Tx [N3402] is faulty.
Replace with a new device.
Example
m_1
The first eight bytes are nor-
mally "00FFFFFFFFFFFF00".
The correct resistor value can-
not be checked if the AVR and
TV are not connected by HDMI.
129
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