I see. Thanks for the explaination. I found my oscilliscope yesterday. However, I cannot find the probe. I think I placed those in some other location. I will try to find those probes today and see what the processor got.
I've had days like that. I STILL haven't found my isolation transformer.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
I found my probes and checked the board.
I connected the probe to both pins of the crystal instead of the processor. The pins on the processor is just so small that I am scared that I will short some pins when I measure.
I seems like there are signals.
Please see the attached pictures.
By the way, I was using channel 2 of the scope.
I found my probes and checked the board.
I connected the probe to both pins of the crystal instead of the processor. The pins on the processor is just so small that I am scared that I will short some pins when I measure.
I seems like there are signals.
Please see the attached pictures.
By the way, I was using channel 2 of the scope.
The amplitude is good, but it looks to me like you have a frequency of about 70 Khz. The doesn't make sense. I would have expected 14 Mhz.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
The amplitude is good, but it looks to me like you have a frequency of about 70 Khz. The doesn't make sense. I would have expected 14 Mhz.
PlainBill
It's unclear whether the x10 is selected on amplitude or TB, Bill. But 2.5div of amplitude at 50mV/div is a bit short.
Certainly that isn't the waveform I'd expect on either xtal pin. Something wrong - wrong pin maybe, or the oscillator circuit trying to excte the xtal? I'd like the OP to zoom in on those included angles after the H-L transitions, as it may be the oscillator trying to start at xtal freq.
It's unclear whether the x10 is selected on amplitude or TB, Bill. But 2.5div of amplitude at 50mV/div is a bit short.
Certainly that isn't the waveform I'd expect on either xtal pin. Something wrong - wrong pin maybe, or the oscillator circuit trying to excte the xtal? I'd like the OP to zoom in on those included angles after the H-L transitions, as it may be the oscillator trying to start at xtal freq.
You could be right; I was assuming a 10X probe.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
Yes, it is 10x probe.
I connected my probe to both pins behind the crystal on the board. Is that how I should connect? I did not connect to the processor.
So how should I change the setting on my scope?
I had a hard time making my scope work. I will take a full picture of the face panel of my scope tonight so that you can have a better idea of what setting I have.
Let's say if the frequency of the crystal is not right, then could it be the crystal not working?
Should I replace the crystal?
Hi Bill, I just saw that you will be having a cataract surgery on May 19, 2010. I wish everything will be going smooth and you will recover soon.
Yes, it is 10x probe.
I connected my probe to both pins behind the crystal on the board. Is that how I should connect? I did not connect to the processor.
So how should I change the setting on my scope?
I had a hard time making my scope work. I will take a full picture of the face panel of my scope tonight so that you can have a better idea of what setting I have.
Let's say if the frequency of the crystal is not right, then could it be the crystal not working?
Should I replace the crystal?
Hi Bill, I just saw that you will be having a cataract surgery on May 19, 2010. I wish everything will be going smooth and you will recover soon.
Connect the scope ground to circuit board ground. Connect the scope probe to either side of the cap. One side should give a stronger signal; use that side.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
I measured it again with the new suggestion.
I turned the TIME/DIV fully clockwise to the CAL'D position.
connect ground of the scope to the board ground and connect the probe to either side of the crystal. The ground of the probe is not connected.
I got some signals. But not matter how I turn the delay, the wave won't stop moving. I cannot stabilize the display.
I measured it again with the new suggestion.
I turned the TIME/DIV fully clockwise to the CAL'D position.
connect ground of the scope to the board ground and connect the probe to either side of the crystal. The ground of the probe is not connected.
I got some signals. But not matter how I turn the delay, the wave won't stop moving. I cannot stabilize the display.
I took a picture of it.
10x probe
.1V/Div
Some suggestions:
1. Upper right corner. Set Sweep Mode to Norm; Source to Ch2.
2. Upper center, set Hor Display to A
3. 'A Time / Div and Delay Time'. Make sure red knob is pushed in and rotated fully clockwise.
4. Adjust Holdoff knobs to stabilize the display. Adjust gray knob under 'A Time / Div and Delay Time' to show several cycles of the waveform.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
Some suggestions:
1. Upper right corner. Set Sweep Mode to Norm; Source to Ch2.
2. Upper center, set Hor Display to A
3. 'A Time / Div and Delay Time'. Make sure red knob is pushed in and rotated fully clockwise.
4. Adjust Holdoff knobs to stabilize the display. Adjust gray knob under 'A Time / Div and Delay Time' to show several cycles of the waveform.
PlainBill
Thx for the suggestion.
A few questions.
Can you explain a little bit more about what the sweep mode, source and hor Display is?
I am always curious about what are those.
Also, on the holdoff knobs, there is a grey small knob on top of the big one. What's the different?
WHen I first got the scope, I was having a hard time stablilzing the screen. So I am thinking it is not working properly. May be I just have the wrong setting.
Thx for teaching me so much.
Nothing that I can think of. Perhaps in the near future, however.
I've got an identical problem with another Dell monitor, a E177FPf. The interesting thing is it's a totally different system. Power supply, inverter and logic all on one board. The processor chip is also different. I'm going to be going over it carefully to see if I can figure out what is going on. The only thing I can think of trying is reinitializing the EEPROM.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
reinitializing the EEPROM?
Sounds like some special programming device is needed.
Not necessarily. On many monitors you can do a reset by holding down certain buttons, then plugging it in. I'm not at all sure that that will work in this case, usually a monitor with a corrupted eeprom will at least flash the power button.
PlainBill
For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.
Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.
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