‫Welcome to the potentiometer your face demonstration with the RTC 7 Film Board I have the potentiometer
‫interface display running on the RTG 7 where I have a 7 segment display all located on the breadboard
‫with 56 ohm resistors connecting each of the segments running back to the RTC 7 on the J Piedmont port.
‫I also have each of the four different digits selects for the 7 segment display connected through a
‫empyrean two and thirty nine or four transistor with a 470 ohm resistor connected at the base.
‫And all of these are fed back into the j b port p.m.-I port of the Arti the seven development board.
‫They also have a potentiometer on the breadboard where three pins the one is connected to ground zero
‫volts.
‫The other is connected to a 3.3 or a high voltage and the output is fed into third wino analog input
‫header on RTC 7 8 0 input and so as I change the potentiometer I should see the reading displayed on
‫the set and segment display and the HD reading is.
‫We have a 12 bit A-D converter so the highest value we can possibly see is four thousand ninety six.
‫And so as I turn the potentiometer we can see the value change on the LCD or on the 7:7 display.
‫So the value to supply there is the HD conversion value that we get that read the analog value and we
‫can convert that.
‫So if I keep going.
‫I should be able to go all the way up to four thousand ninety six however will see that as I keep going
‫up to about three thousand eight hundred eighty eight and this is because we have there are several
‫different things going on.
‫We can get exactly three point three bolts one some of the voltage is dropped across potentiometer as
‫well as the the resistors and capacitors are located on the RTC setting.
‫And also if you'll notice as I turn the last digit stays an 8 and that's because the sampling is so
‫precise that we're sample two hundred thousand samples a second.
‫So that's updating so fast that it looks like an 8 because every single segment gets lit up when it
‫becomes a 0 1 2 all the way up to 9.
‫But you'll see the farther to the date the digits go out as we change the tensiometer value that those
‫are a lot more stable.
‫And so that is what the that's how the potential our interface should be running on the Arties the 7.