Instructions

THE VARIABLE RESISTOR
The main component of the Slider for micro:bit is a sliding variable resistor (also
often called a potentiometer or just pot). The other components on the board are
designed to protect your micro:bit against accidental damage should you connect
things the wrong way around and the amber power LED that show that the Slider
for micro:bit is powered.
Here's the schematic diagram of a variable resistor and micro:bit working together.
The variable resistor is actually a resistive track, across which the micro:bit supplies
a voltage of 0V at one end (the left) and 3V at the other (right). When you move the
slider left and right you are moving a sliding electrical contact along the track. When
the slider is at its leftmost position, the voltage at the slider will have a voltage of 0V
and when its at the rightmost position the slider will have a voltage of 3V. When its
in the middle position, this voltage will be half way between 0 and 3V in other words
1.5V. Note that the actual voltage will probably be less than 3V if you are powering
the micro:bit from batteries.
The slider voltage is measured by the micro:bit using P2 (or whichever pin you
decide to use) as an analog input.
The three connections 0, 1 and 2 can all be used as analog inputs. In Blockcode,
you do this using the analog read pin block. This block measures the voltage at the
connector specified but rather than return the actual voltage in Volts, it returns a
number between 0 and 1023.
When the slider is in its leftmost position, the reading will be 0 and when rightmost
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