Editing AMD Geode/Video 1/Script
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Voice: "Ideally I'd use a period accurate IBM PC" | Voice: "Ideally I'd use a period accurate IBM PC" | ||
A screenshot of expensive eBay listings scrolls past. One is shown to cost $500 AUD. | |||
Voice: "But these are really expensive" | Voice: "But these are really expensive" | ||
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The monitor is shown again with the text "No Signal" displayed. | The monitor is shown again with the text "No Signal" displayed. | ||
The board is shown with a chip marked | The board is shown with a chip marked 'V1.18' removed from its socket. | ||
Voice: "I removed the BIOS chip to see if it would still beep. It didn't." | Voice: "I removed the BIOS chip to see if it would still beep. It didn't." | ||
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Voice: "Next I looked at the clock battery." | Voice: "Next I looked at the clock battery." | ||
A multimeter is shown with its probes touching the positive and negative sides of the battery. It displays the value | A multimeter is shown with its probes touching the positive and negative sides of the battery. It displays the value 198mV. | ||
Voice: "My multimeter showed it was around | Voice: "My multimeter showed it was around 200mV. Completely dead." | ||
A close up of the battery being held by pliers is shown. The brand name RAYOVAC and the text "LITHIUM 3V BR1632 USA" is engraved on the chip. | A close up of the battery being held by pliers is shown. The brand name RAYOVAC and the text "LITHIUM 3V BR1632 USA" is engraved on the chip. | ||
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Voice: "Perhaps a dead battery corrupted the BIOS settings somehow?" | Voice: "Perhaps a dead battery corrupted the BIOS settings somehow?" | ||
The second monitor is shown again, this time with an orange plastic frog glowing on the desk near it. The monitor still says "Input Not Support" | The second monitor is shown again, this time with an orange plastic frog glowing on the desk near it. The monitor still says "Input Not Support" | ||
Voice: "Running without the battery didn't help." | Voice: "Running without the battery didn't help." | ||
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An oscilloscope probe goes in to one of the breadboard holes. | An oscilloscope probe goes in to one of the breadboard holes. | ||
The oscilloscope screen shows a signal at | The oscilloscope screen shows a signal at 0v raising to 5v briefly then dropping down to -5v. | ||
Voice: "Probing it showed the serial line was initialized, but it wasn't outputting anything." | Voice: "Probing it showed the serial line was initialized, but it wasn't outputting anything." | ||
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Voice: "At this point I figured it was time to check the VGA signals." | Voice: "At this point I figured it was time to check the VGA signals." | ||
An oscilloscope screen shows a | An oscilloscope screen shows a 0v signal with shorts jump between 6.80v and -2.56v. | ||
Voice: "I started with vertical sync, this signal pulses every frame." | Voice: "I started with vertical sync, this signal pulses every frame." | ||
The camera zooms in to show the frequency of the signal is 60. | The camera zooms in to show the frequency of the signal is 60.00Hz and the period is 16.67ms. | ||
Voice: "Around 60 times a second." | Voice: "Around 60 times a second." | ||
The oscilloscope shows a a | The oscilloscope shows a a 5V wide square wave with cursors measuring the wave. The wave is around 5v, peaking at 5.57v 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 24.75KHz. | ||
Voice: "Looking at a single pulse we can see that it's a 5 volt square wave lasting for around 40 microseconds." | 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. | The oscilloscope shows the leading edge of the square wave. It peaks at 6.64v and takes 228ns to settle to 4.64v. | ||
Voice: "The pulse seems to peak around 6.6 volts and takes around 230 nanoseconds to settle. This all look fine to me." | Voice: "The pulse seems to peak around 6.6 volts and takes around 230 nanoseconds to settle. This all look fine to me." | ||
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Voice: "Next is horizontal sync." | Voice: "Next is horizontal sync." | ||
The oscilloscope shows a | The oscilloscope shows a 0v signal with longer jumps between 6.64v and -2.40v. The camera zooms in to show frequency is 75.02KHz and the period is 13.33 microseconds. | ||
Voice: "This signal pulses every row of pixels. Around 75 kilohertz in our case." | Voice: "This signal pulses every row of pixels. Around 75 kilohertz in our case." | ||
The oscilloscope shows a | The oscilloscope shows a 5V wide square wave with cursors measuring the wave. The wave peaks at 6.55v at the leading edge and -2.41v on the trailing edge. The time a pulse takes is 1.45 microseconds, or 692.0KHz. | ||
Voice: "Looking closer we can see the pulse is the same voltage as the vertical sync and it lasts around 1.45 microseconds." | 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. | The oscilloscope shows the leading edge of the square wave. It peaks at 6.60v and takes 197ns to settle to 4.86v. | ||
Voice: "The pulse takes 197 nanoseconds to settle high" | Voice: "The pulse takes 197 nanoseconds to settle high" | ||
The oscilloscope shows the trailing edge of the square wave. It drops to -2. | The oscilloscope shows the trailing edge of the square wave. It drops to -2.51v and takes 307ns to settle to -51.20mV. | ||
Voice: "and 307 nanoseconds to settle low. This looks completely fine as well." | Voice: "and 307 nanoseconds to settle low. This looks completely fine as well." | ||
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Voice: "Ok, red signal" | Voice: "Ok, red signal" | ||
The oscilloscope shows a flat line with a max voltage of | The oscilloscope shows a flat line with a max voltage of 280mV and minimum of -360mV. | ||
Voice: "I don't actually see any signal" | Voice: "I don't actually see any signal" | ||
The camera zooms to show a max voltage of | The camera zooms to show a max voltage of 200mV and minimum of -120mV. | ||
Voice: "It just stays around 200 millivolts." | Voice: "It just stays around 200 millivolts." | ||
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Voice: "Okay, green" | Voice: "Okay, green" | ||
The oscilloscope shows a flat line with a max voltage of | The oscilloscope shows a flat line with a max voltage of 160mV and minimum of -80mV. | ||
Voice: "Same thing but it's around 160 millivolts this time." | Voice: "Same thing but it's around 160 millivolts this time." | ||
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Voice: "What about blue?" | Voice: "What about blue?" | ||
The oscilloscope shows a flat line with a max voltage of | The oscilloscope shows a flat line with a max voltage of 280mV and minimum of -160mV. | ||
Voice: "It's the same thing as red and green. These all should be much higher." | Voice: "It's the same thing as red and green. These all should be much higher." | ||
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== SD card adapter == | == SD card adapter == | ||
An IDE to SD card adapter is shown on the table, with an SD card inserted. Its circuit board is black and yellow and the main chip on the board has a | An IDE to SD card adapter is shown on the table, with an SD card inserted. Its circuit board is black and yellow and the main chip on the board has a 'QC Passed' sticker that changes color based on the angle. | ||
Voice: "I did try to connect an IDE to SD card adapter so I could boot from it." | Voice: "I did try to connect an IDE to SD card adapter so I could boot from it." |