book

Building iPhone and iPad Electronic Projects

by Mike Westerfield

September 2013

Intermediate to advanced

332 pages

8h 30m

English

O'Reilly Media, Inc.

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Conventions Used in This BookUsing Code ExamplesSafari® Books OnlineHow to Contact UsAcknowledgmentsCredits
Your Own TricorderA Crash Course in techBASICtechBASIC SamplerRunning Your First ProgramCreating a ProgramThe Accelerometer
The GyroscopeRadians or Degrees?The MagnetometerFaster Sensor ResponseHeadingLocationYour Own Tricorder
The iPhone/iPad MagnetometerThe Earth’s Magnetic FieldUsing the iPhone or iPad as a Metal DetectorConverting the Magnetometer Sample into a Metal DetectorUsing the Metal DetectorFinding Out More
What Is HiJack?Building the SensorExternal Power for HiJackHello HiJackWhen Things Go WrongA Better HiJack ProgramFor More Information
Adding a Moisture Meter to the TricorderAssembling the Moisture MeterCalibrationCollecting the Calibration DataMoving Datafiles to and from techBASICUsing the Calibration DataBetter SoftwareThe Complete Moisture Meter Source
What Is Bluetooth Low Energy?The TI SensorTagWriting Bluetooth Low Energy ProgramsThe AccelerometerWhat’s an Accelerometer?Accessing the AccelerometerUsing the AccelerometerThe SourceThe BarometerAccessing the BarometerThe SourceThe GyroscopeAccessing the GyroscopeUsing the GyroscopeThe SourceThe MagnetometerAccessing the MagnetometerUsing the MagnetometerThe SourceThe Humidity Sensor (Hygrometer)Accessing the HygrometerThe SourceThe ThermometerAccessing the ThermometerUsing the ThermometerThe SourceFurther Explorations
A Bit of Rocket ScienceParts ListsST-1ST-2Other Items for Both RocketsWhy Use a SensorTag?ConstructionST-2: The iPhone/SensorTag RocketST-1: The SensorTag RocketThe Data Collection ProgramSensorTag 8G SoftwareFlight TipsEnginesParachutesFlight ConditionsPower Up!The DataAnalyzing the DataRocket Data AnalysisVelocity and AltitudeRotation and PressureWhat We FoundST-1 ResultsST-2 Results
Controlling a Truck with BLESelecting a TruckDisassemblyHacking the TruckThe H BridgeThe TI ChipWiring the Complete CircuitControlling the Arduino UnoInstalling ArduinoDownloading FirmataInstalling FirmataThe SoftwarePulse Width ModulationState enginesBack to the SoftwareStart Your Engines!
Bluetooth Low Energy Slave ModeBLE ChatSetting Up the ServicesUsing the Services

The Classic Game of PongThe Paddles GameThe Paddle SoftwareThe Paddles Console Software
Worldwide SensorsHTTP, FTP, and TCP/IPWiFlyThe CircuitEstablishing a Network ConnectionCommunication with TCP/IPA Simple Terminal ProgramWiFi ArduinoLoading Software onto the ArduinoThe CircuitCommunication Using the Terminal Program
Servos: They’re Where the Action IsThe Pololu Serial Servo ControllerThe CircuitHalloween HijinksThe SoftwareTake It for a SpinPush and Pull with ServosPomp and Circumstance

Content preview from Building iPhone and iPad Electronic Projects

Chapter 4. HiJack

Prerequisites

Read Chapter 1 and the end of Chapter 2 (the section on the techBASIC help system) if you need some help with techBASIC. If you are already comfortable with techBASIC, jump right in.

Equipment

You will need an iPhone, iPod, or iPad running iOS 5 or later. You will also need a HiJack device from Seeed Studio and various common electronics parts like wires, resistors, and a potentiometer. See Table 4-1 for a complete parts list.

Newer iPhones and all iPads give out less power through the headphone port than the original devices HiJack was designed for. You may end up needing an external power supply. See Table 4-2 for the parts needed to build one kind of power supply.

Software

You will need a copy of techBASIC or techBASIC Sampler.

What You Will Learn

This chapter introduces HiJack, a device that supports an eight-bit analog-to-digital (A–D) converter plugged into the headphone port. It’s the only wired technology Apple allows general-purpose apps to support.

What Is HiJack?

HiJack (shown in Figure 4-1) is a hardware device that plugs right into your iPhone, iPad, or iPod headphone jack. It’s the only wired technology that can connect to iOS devices that isn’t controlled by Apple’s MFi program. This means it is also the only wired technology for which Apple will approve apps for the App Store without going through the MFi program.

Figure 4-1. HiJack is a wired technology for sensor input