What would you do with a single shield that has an accelerometer, speaker, microphone, infrared transmitter, infrared receiver, RGB LED, four discrete LED’s, two pushbuttons, a potentiometer, and a visible light sensor?
The Gadget Shield is an add-on (shield) compatible with the Arduino Uno, Duemilanove, Mega/Mega2560, Ruggeduino, or other compatible boards. It extends the functionality of the microcontroller board by adding several interesting sensors and actuators. Fully assembled and ready to go, the Gadget Shield opens up a whole world of fun and learning.
The Gadget Shield comes with a wide variety of sensors and actuators
Arduino Uno/Duemilanove
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The Gadget Shield is shown mounted on an Arduino Duemilanove (also compatible with the Uno, Mega/Mega2560, and Ruggeduino). The RGB LED has its blue LED turned on (at just 12% of its maximum brightness!) and the 4 general-purpose LED's are illuminated.
Arduino Mega
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The Gadget Shield is shown mounted on an Arduino Mega
Stacking Headers
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The Gadget Shield uses stacking headers, meaning you can plug more shields on top of it. This picture shows a Duemilanove with a Gadget Shield and a Rugged Motor Driver on top. Control your motor with an infrared remote control? Why not!
External Power Input
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A 2-pin terminal block easily allows external power connections for battery-powered installations.
The Gadget Shield
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The Gadget Shield comes fully assembled and ready to use, compatible with the Arduino Uno, Duemilanove, Mega/Mega2560, Ruggeduino, and other compatible boards
$29.95
Features
The Gadget Shield includes:
A Freescale MMA7660FC 3-axis digital accelerometer
This is a 1.5g 120 sample-per-second digital accelerometer with 6-bit resolution and neat features such as tap/shake detection and tilt/orientation detection. Here is a direct link to the Freescale datasheet.
A high-brightness RGB LED
This module contains three independent LED’s (red, green, and blue) with independent brightness control for each color since each LED is connected to a separate microcontroller PWM output. This gives you an incredibly wide color palette to choose from. This thing is bright -- the manufacturer does not recommend looking directly at it when operating at maximum power, and we usually just run it at about 10%-20% duty cycles because that’s plenty bright.
A 38 kHz logic infrared detector
This module outputs a digital low signal when 38kHz-modulated infrared energy is detected, as output by most infrared remote controls. See our sample software for using this module to decode infrared remote control transmissions. Together with the infrared LED emitter, this can be also be used as a non-contact object sensor (again, we have some sample software that demonstrates this).
An infrared LED
This LED emits light in the 940nm wavelength range and can be used to generate infrared remote control signals. This LED is controlled by a microcontroller timer pin so it is simple to generate the 38 kHz frequencies recognized by most receivers. See our sample software for using this LED together with the IR logic detector to turn your microcontroller board into a universal remote control.
A speaker
Use this to generate tones, alerts, or to play simple melodies (see our sample software below). The speaker uses PWM to generate frequencies up to 3000 Hz.
A microphone
Use this for sound sensing or tone detection. The microphone’s raw output is amplified (gain of 100), low-pass filtered to 15.9 kHz, offset by 2.5V then connected to an A/D input pin.
A visible light sensor
This device outputs an analog signal inversely proportional to the intensity of visible light (more light means lower voltage). This signal is connected to an A/D input pin.
A thumbwheel potentiometer
The potentiometer’s rotation can be read using an A/D input pin.
Four LED’s
4 general-purpose LED’s are connected to four independent digital outputs (active high) for displaying status information, or perhaps a 4-bit binary value. We use these LED’s as a “VU meter” for displaying light level and sound level in our sample software below.
Two pushbuttons
Two general-purpose momentary-contact pushbuttons are connected to two independent digital inputs (active low).
Two-pin terminal block for external voltage input
For battery-powered operation or self-contained installations, it can be a pain to power an Arduino and its shields. The Gadget Shield makes this a little easier by providing a two-pin screw terminal block for easily connecting wire leads from battery packs or other power supplies. This voltage connects to the Vin node on the Arduino (through a reverse-voltage-blocking diode -- see the schematic) so is the same as plugging in a DC power jack.
Stacking Headers
Stacking headers let you stack another shield on top of the Gadget Shield, or you can plug wires right into each header socket for direct control over the on-board gadgets.
Cuttable Jumpers
What if you don’t want to use the microphone and want to reclaim analog pin A0 for something else? No problem! Every pin connection on the Gadget Shield goes through a cuttable jumper that is easily cut with a hobby knife. The Arduino pin is then disconnected from that pin’s gadget. You can then use the Arduino pin for something else by connecting to it through the stackable header. Changed your mind? Just short the jumper by soldering in a small wire, or solder in a two-pin 0.1” header and use a shunt to re-make the connection. More details below.
Arduino Library
The Gadget Shield comes with an Arduino library to help you get started quickly.
Download the latest GadgetShield library for Arduino 1.0, or this version of the GadgetShield library for Arduino-0022.
Unzip it in the libraries directory of your Arduino installation. See the Contributed Libraries section of this reference page for help with installing third-party libraries.
Documentation for the library is in the GadgetShield.h header file, or see the sample code below for usage examples. Here’s a quick taste to show you how easy it is to work with the Gadget Shield. This sketch plays a tone on the speaker whenever pushbutton #1 is pressed.
/* Play a tone on the speaker whenever pushbutton #1 is pressed */
#include <GadgetShield.h>
void setup(void) {
GS.Setup();
}
void loop(void) {
if (GS.IsSwitch(0)) GS.Speaker(440);
else GS.Speaker(0);
}
Sample Code
Here are some sample programs for demonstrating the applications of the Gadget Shield. These sketches are also included as part of the GadgetShield library described above.
Object Detector
The IR LED and detector are good for more than just remote control. Since they are both pointing in the same direction you can use them together as an object detector. Turn on the IR LED at 38 kHz, then if an object reflects the IR light back to the detector, you will be able to sense that the IR detector’s output is low. Download this sketch and try it out for yourself! Instructions are at the top of the file.
This demonstrates the infrared logic detector and emitter by constructing a simple universal remote. Instructions are provided at the top of the PDE file. Once you teach the application what one or more buttons do on your remote, you can then either have the application recognize them when pressed again, or have the application output them on command. Use this application as a starting point for your own IR control applications.
This fun application demonstrates how the 3-dimensional orientation of the Gadget Shield can be sensed using the on-board accelerometer. The orientation is used to control the color of the RGB LED module.
This application is what we use for production testing. It exercises every sensor and actuator on the Gadget Shield. Use it as an example for how to interface with all of the devices on the board. Instructions are at the top of the PDE file.
The Arduino Mega and Mega2560 have the two TWI pins (SCL and SDA) in a different place than the Arduino Uno and Duemilanove. These two pins are needed for communicating with the accelerometer. To use the accelerometer with a Mega, you will need to connect two wires to jumper the SCL and SDA pins from the Mega header to the Gadget Shield header. There are two ways to do this, directly to the stacking header pins A4/A5 or to a special two-pin header location (JP1) which is also connected to A4/A5. The figures below show these possibilities.
Connect SDA/SCL on a Mega by directly connecting to header pins A4/A5
or
Connect SDA/SCL on a Mega by connecting to a separate header JP1
Note that to connect to JP1 you will either need to solder the wires there for a permanent connection or solder in a two-pin 0.1” socket header (not included).
If you are not using the accelerometer on the Gadget Shield then these two wire connections are not needed.
Pin Mapping
The pin usage of the various sensors and actuators on the Gadget Shield is shown in the following table.
All of the Arduino pins connect to the gadgets through cuttable jumpers on the bottom side of the board. Here is a picture of part of the board bottom:
If you don’t want to use a particular gadget but you want to use an Arduino pin for something else, cutting the gadget’s jumper lets you do so. If you want to reconnect it, just make a solder bridge over your cut, solder in a short bare wire, or solder in a 2-pin 0.1” jumper and use a shunt to make a removable connection.
You can also use the cuttable jumpers as cross-wiring points. Suppose you really don’t like the pin mapping we have chosen. You can use cuts and wires over our cuttable jumpers to create your own pin mapping.
Here is a picture of the PCB layout on the bottom of the board showing where all cuttable jumpers are. The connector numbers (J1, J2, etc.) refer to the jumper names shown in the schematic.
J21 is a normally-open jumper that you can connect to make a connection between +3.3V and the AREF pin for the analog-to-digital converter. This is just a handy way to create an alternative reference voltage for the converter.
External Power Input
For standalone or battery-powered operation, the two-pin terminal block allows you to make a sturdy connection to a battery or other power source, without having to insert wires into stacking headers and hope they stay put.
This power input is essentially the same as the DC power jack on the Arduino. Provide a DC power source of the same voltage and current that is required by your Arduino board (e.g., 7-12VDC for an Arduino Uno, at least 100mA is recommended). The power input is reverse-voltage protected by a diode, just like the DC power jack input on the Arduino. Power you apply to the two-pin terminal block is available at the Vin pin on the stacking headers.
Technical Data
Here is the schematic of the Gadget Shield. Here is the schematic of the previous revision (part number AS010).
The Gadget Shield was designed in the USA and is assembled in the USA using lead-free components and lead-free manufacturing and assembly processes.
