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‫Welcome to the potentiometer interface demonstration but the base is three board for this demonstration.

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‫We have a potentiometer connected to an external breadboard with three 2.2 K ohm resistors and with

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‫these resistors we are creating a voltage divider where we are taking the three point three bolts and

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‫dividing it by three.

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‫So we get down to approximately one volt and that is because the X A.D.C. on the core in the Artic seven

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‫chip on the basis your board can only read voltages from 0 to 1 volt.

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‫And with that being said we're putting 3.3 volts into the X ADC PMA port.

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‫So we have to create a voltage divider so that when we're at 3.3 volts We're actually only output 1

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‫volt.

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‫And so what we'll do as I turn the potentiometer the ADC reading inside the Artic seven chip on base

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‫3 board is being displayed in a BCT format on the 7 segment display.

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‫And the ADC core on the Artic 7 is a 12 bit 8 of the converter.

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‫So the maximum output it can have is four thousand ninety six.

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‫And so right now we're at like 8 8 or 0 and that's just because you can't get exactly zero.

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‫We're sampling so fast we're currently sampling at 200 thousand samples per second.

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‫So it's happening so quickly.

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‫They appear to all be lit up as I start to turn the potentiometer.

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‫You can see the values start to change.

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‫Now we're at like a 4 5 7 1 1 8 8.

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‫And the last two values are sincerely significant values change so fast that it appears there are a

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‫constantly.

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‫And so if I keep turning up that showing the voltage is getting higher and higher and you can see the

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‫corresponding ADC reading goes up as well.

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‫And if I turn the other way it goes down and if I go all the way over we get up to approximately 3 9

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‫8 8 and that's just because we do have some losses from the three point supply we are currently using

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‫some across these resistors we're having here to do a voltage divider boom we turn all the way over

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‫we'll get up pretty close and end and each board is going to be slightly different just due to the 3.3

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‫regulations supply they have.

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‫But you should see somewhere close to 4000 as your maximum on the potential on the ATC reading.

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‫And that is the potentiometer interface running on the bases three all board.