Arduino Microcontroller

Red Box Contents

Breadboard

Jumper Wires

Flex SensorAs the sensor is flexed, the resistance across the sensor increases. Patented technology by Spectra Symbol - they claim these sensors were used in the original Nintendo Power Glove.

The resistance of the flex sensor changes when the metal pads are on the outside of the bend (text on inside of bend).

Connector is 0.1" spaced and bread board friendly.

SoftPotMeasure position along the softpot by looking at the change in resistance.

It's like a touch sensitive volume slider.

Photocell

This is a very small light sensor. A photocell changes (also called a photodetector, photo resistor, CdS or photoconductive cell) resistance depending on the amount of light it is exposed to. These little sensors make great ambient light triggers (when light in the room turns on, do something).

Thermistor10K thermistor with a negative temperature coefficient. Good choice for temp-sensing applications.

Tri-Color LEDEver hear of a thing called RGB? Red, Green, Blue? How about an RGB LED? These 5mm units have four pins - Cathode is the longest pin. One for each color and a common cathode. Use this one LED for three status indicators or pulse width modulate all three and get mixed colors.

Linear Trimmer PotThis 10K trimmable potentiometer has a small knob built right in and it's breadboard friendly to boot! Perfect for your next LCD contrast adjuster, opamp setting, or volume level.

BuzzerThis is a small 12mm round buzzer that operates around the audible 2kHz range.

ButtonThis is a standard 12mm square momentary button.

What is Debouncing?• Bouncing is the tendency of any two metal

contacts in an electronic device to generate multiple signals as the contacts close or open.

• Debouncing is any kind of hardware device or software that ensures that only a single signal will be acted upon for a single opening or closing of a contact.

What is Pulse Width Modulation?• Pulse Width Modulation, or

PWM, is a technique for getting analog results with digital means.

• To get varying analog values, you change, or modulate, that pulse width of a square wave.

• If you repeat this on-off pattern fast enough with an LED for example, the result is as if the signal is a steady voltage between 0 and 5v controlling the brightness of the LED.

How does a Flex Sensor work?• One side of the sensor is

printed with a polymer ink that has conductive particles embedded in it.

• When the sensor is straight, the particles give the ink a lower resistance.

• When the sensor is bent away from the ink, the conductive particles move further apart, increasing this resistance.

How does a SoftPot work?• In simple terms, the SoftPot membrane potentiometer is a

resistive element, which comprises a conductive resistor, a sealed encasement and a simple wiper assembly.

What is a pull-up or pull-down resistor?• Pull-up resistors are used in electronic logic

circuits to ensure that inputs to logic systems settle at expected logic levels if external devices are disconnected or high-impedance is introduced.

Final Exam• Monday, May 11– 12:30PM and 2:00PM Start Times– Be thinking about which time you would like to

start.– There will be a 60 minute time limit for the circuit

construction. (The circuit must be re-constructed on the day of the exam.)

Final Exam• Code Commenting– Use \\ and \* *\ to add comments to your code.– The comments must include that name of the INO

file.– The top comment section must explain how each

components (resistors, buzzer, LED, etc.) is connected to the circuit.

– Know how to identify which pins allow for pulse width modulation.

– Make a sketch of the circuit prior to the final exam using the app available at www.fritzing.org.

Final Exam