The Vinco Touch Key applications board, which the supplier calls a shield mates with the Vinco motherboard, and incorporates a STMicroelectronics STMPE821 8-channel general purpose input/output (GPIO) capacitive touch key controller IC.
The shield has 8 touch keys which employ a capacitive sensing technology, responding to physical input stimulus from the user. It also has a set of 4 push buttons and 5 GPIO-controlled LED indicators.
The touch keys are capable of passing input data to the Vinculum-II (VNC2) dual port USB host/device controller IC on the Vinco module via an I2C bus, where it can be processed by the IC’s integrated 16-bit microcontroller core.
Access to the Vinco pulse width modulation (PWM) interface is also available on the header pins. The shield requires a 5V supply, which can be drawn from an external supply or through the Vinco motherboard connections.
“The new Touch Key shield demonstrates the Vinco platform’s ability to utilise the Android Open Accessory initiative, so that devices using the Android operating system, such as tablet PCs, can control items of external hardware through a human machine interface (HMI), over USB,” said Dave Sroka, global product director at FTDI.
The shield is supplied in a 55.4 mm x 68.6 mm form-factor, the established format of the Arduino Duemilanove and Uno boards.
There are free software libraries, drivers and source code. An Integrated Development Environment (IDE) includes a code editor, ‘C’ compiler, assembler and debugger.
The FTDI Vinco Touch Key shield is available at a cost of $33.75 for single units.
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