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AMD Geode/Video 1/Script
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== VGA probing == An oscilloscope probe is shown entering a hole on the VGA connector. Voice: "At this point I figured it was time to check the VGA signals." An oscilloscope screen shows a 0 volt signal with shorts jump between 6.80 volts and -2.56 volts. Voice: "I started with vertical sync, this signal pulses every frame." The camera zooms in to show the frequency of the signal is 60.00 hertz and the period is 16.67 milliseconds. Voice: "Around 60 times a second." The oscilloscope shows a a 5 volt square wave with cursors measuring the wave. The wave is around 5 volt, peaking at 5.57 volts on the leading edge and dropping down to some unknown voltage on the trailing edge. The time a pulse of the wave takes is 40 microseconds, or 24.75 kilohertz. Voice: "Looking at a single pulse we can see that it's a 5 volt square wave lasting for around 40 microseconds." The oscilloscope shows the leading edge of the square wave. It peaks at 6.64 volts and takes 228 nanoseconds to settle to 4.64 volts. Voice: "The pulse seems to peak around 6.6 volts and takes around 230 nanoseconds to settle. This all look fine to me." An oscilloscope probe is shown entering another hole on the VGA connector. Voice: "Next is horizontal sync." The oscilloscope shows a 0 volt signal with longer jumps between 6.64 volts and -2.40 volts. The camera zooms in to show frequency is 75.05 kilohertz and the period is 13.33 microseconds. Voice: "This signal pulses every row of pixels. Around 75 kilohertz in our case." The oscilloscope shows a 5 volt wide square wave with cursors measuring the wave. The wave peaks at 6.55 volts at the leading edge and -2.41 volts on the trailing edge. The time a pulse takes is 1.45 microseconds, or 692.0 kilohertz. Voice: "Looking closer we can see the pulse is the same voltage as the vertical sync and it lasts around 1.45 microseconds." The oscilloscope shows the leading edge of the square wave. It peaks at 6.60 volts and takes 197 nanoseconds to settle to 4.86 volts. Voice: "The pulse takes 197 nanoseconds to settle high" The oscilloscope shows the trailing edge of the square wave. It drops to -2.51 volts and takes 307 nanoseconds to settle to -51.20 millivolts. Voice: "and 307 nanoseconds to settle low. This looks completely fine as well." An oscilloscope probe is shown entering another hole on the VGA connector. Voice: "Ok, red signal" The oscilloscope shows a flat line with a max voltage of 280 millivolts and minimum of -360 millivolts. Voice: "I don't actually see any signal" The camera zooms to show a max voltage of 200 millivolts and minimum of -120 millivolts. Voice: "It just stays around 200 millivolts." An oscilloscope probe is shown entering another hole on the VGA connector. Voice: "Okay, green" The oscilloscope shows a flat line with a max voltage of 160 millivolts and minimum of -80 millivolts. Voice: "Same thing but it's around 160 millivolts this time." An oscilloscope probe is shown entering another hole on the VGA connector. Voice: "What about blue?" The oscilloscope shows a flat line with a max voltage of 280 millivolts and minimum of -160 millivolts. Voice: "It's the same thing as red and green. These all should be much higher." The underside of a PCB is shown with the VGA connector's solder joints visible. Voice: "Just to be sure I wasn't missing something obvious I took a look at the VGA section of the board." The top of the PCB is shown with a probe pointing at an area containing various tiny components next to the connector. Voice: "I didn't see any visible issues at all."
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