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‫Welcome to the potentiometer your face demonstration with the RTC 7 Film Board I have the potentiometer

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‫interface display running on the RTG 7 where I have a 7 segment display all located on the breadboard

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‫with 56 ohm resistors connecting each of the segments running back to the RTC 7 on the J Piedmont port.

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‫I also have each of the four different digits selects for the 7 segment display connected through a

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‫empyrean two and thirty nine or four transistor with a 470 ohm resistor connected at the base.

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‫And all of these are fed back into the j b port p.m.-I port of the Arti the seven development board.

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‫They also have a potentiometer on the breadboard where three pins the one is connected to ground zero

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‫volts.

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‫The other is connected to a 3.3 or a high voltage and the output is fed into third wino analog input

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‫header on RTC 7 8 0 input and so as I change the potentiometer I should see the reading displayed on

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‫the set and segment display and the HD reading is.

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‫We have a 12 bit A-D converter so the highest value we can possibly see is four thousand ninety six.

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‫And so as I turn the potentiometer we can see the value change on the LCD or on the 7:7 display.

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‫So the value to supply there is the HD conversion value that we get that read the analog value and we

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‫can convert that.

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‫So if I keep going.

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‫I should be able to go all the way up to four thousand ninety six however will see that as I keep going

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‫up to about three thousand eight hundred eighty eight and this is because we have there are several

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‫different things going on.

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‫We can get exactly three point three bolts one some of the voltage is dropped across potentiometer as

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‫well as the the resistors and capacitors are located on the RTC setting.

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‫And also if you'll notice as I turn the last digit stays an 8 and that's because the sampling is so

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‫precise that we're sample two hundred thousand samples a second.

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‫So that's updating so fast that it looks like an 8 because every single segment gets lit up when it

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‫becomes a 0 1 2 all the way up to 9.

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‫But you'll see the farther to the date the digits go out as we change the tensiometer value that those

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‫are a lot more stable.

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‫And so that is what the that's how the potential our interface should be running on the Arties the 7.