The IOIO-OTG (pronounced "yo-yo-O-T-G") is a development board that lets Java developers add hardware I/O capabilities to Android or PC applications. A PIC24FJ256 microcontroller bridges your app to low-level peripherals including GPIO, PWM, ADC, I²C, SPI, and UART, all controllable through a Java library.

The OTG (On-The-Go) design supports both USB host and device modes. When connected to an Android device, the board acts as a USB host and supplies charging current. When connected to a PC (Windows, Linux, or macOS), it presents as a virtual serial port and draws power from the host. Attach a USB Bluetooth dongle for wireless connectivity.

Key Features

• USB OTG Support – Auto-detects host or device mode (manual override switch available)
• Java Control Library – Write hardware control code as a standard Java app
• Rich Peripheral Access – GPIO, PWM, ADC, I²C, SPI, and UART
• Cross-Platform – Works with Android, Windows, Linux, and macOS
• Bluetooth Ready – Connect a USB Bluetooth dongle for wireless serial
• LiPo Battery Connector – JST connector with adjustable charge current (trimpot)
• Field-Upgradeable Firmware – Update via the IOIODude application (no programmer needed)

Ideal For

• Android hardware accessories and peripherals
• PC-based data acquisition and control
• Robotics with Java-based control software
• Rapid prototyping of USB-connected hardware

Package Contents

• 1× IOIO-OTG Development Board (V2.2b)
• 1× USB Female-A to Micro-A OTG cable

Resources

• Hookup Guide
• IOIO Wiki
• IOIODude Firmware Updater
• PIC24FJ256 Datasheet (PDF)
• Operating Modes Application Note (PDF)
• Schematic (PDF)
• Design Files (GitHub)