Basic Electronics
Voltage (V or E): Potential difference
between 2 points. Volts.
• (+) - A lack of electrons
• (-) – A surplus of electrons
• When a circuit is formed, electrons will flow
to equalize out the 2 sides.
Current (I): The measure of the flow of
electrons. Amps.
Resistance (R): Opposition to current
flow. Ohms.
Ohm's Law: I = V/R
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Resistors
Devices used to insert resistance, or
oppose current flow. Used to limit
current flow.
Color codes are used to indicate the
value.
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From Appendix C
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The LED
LED: Light Emitting Diode
Diode: Device which allows current to
flow in only one direction.
To operate, is must be installed correctly
with respect to polarity.
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A regular LED can be damaged if current
exceed 20mA (milliamps).
Apply ohm's law to find the resistor size
that will limit current to 20mA
with a 5V supply.
I = V/R
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LED Circuit Schematic
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The BreadBoard
Breadboards are used to make
connections between devices.
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Building the Circuit
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Pictorial or Wiring Diagram
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Code to Blink LEDs
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Task
Perform Chapter 2 up to this point (page
52), including "Your Turn- Blink the other
LED"
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Additional – The Speaker/Buzzer
A small piezoelectric speaker is included
with your kits.
A frequency can be sounded on it using
the FREQOUT command.
FREQOUT pin, duration, frequency
• pin: Pin it is connected to.
• duration: Length of time in milliseconds.
• frequency: Frequency to play, measured in
Hertz (Hz).
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Sound the Speaker for 1 second at 1000Hz
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Group Task
Write a program that will:
• Display in DEBUG Window
"Stop! Police!"
• Turn ON P12 LED
• Sound a tone for ½ second at 1000Hz
• Turn OFF P12 LED
• Turn on P13 LED
• Sound a tone for ½ second at 2000Hz
• Turn off P13 LED
• Repeat sequence
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Individual Task
Develop a program to act as a "Ray Gun"
movie prop. Use appropriate lights and
sound sequences.
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