MINI-IO

in Blog

2 April 2014

A sensor network development platform for art installations, interactive music and dance performances, immersive museum exhibits, theatre productions etc.

MINI-IO provides an easy way to develop sensor networks that need to cover large areas. Each MINI-IO has 4 12-bit analog inputs and a digital expansion port. Up to 32 MINI-IOs can be daisy-chained together using standard Cat5 cable. The maximum distance between the first and the last MINI-IO in a chain is 500 meters. A chain of one or more MINI-IOs connects to a computer using the included USB adapter, which also powers the MINI-IO chain (and the attached sensors) from a single point.

MINI-IO uses pluggable terminal block connectors for fast and easy prototyping. Each analog input has GND and +5V connections. MINI-IO is designed to be as unobtrusive as possible, and measures just 34mm x 34mm. Mounting holes allow for easy attachment to a variety of objects using low-cost 3mm diameter PCB posts or M3 size screws.

The digital expansion port is compatible with digital sensors such as MaxSonar ultrasonic proximity sensors and any I2C, SPI or asynchroneous serial device. Alternatively, the expansion port provides four digital inputs with internal pull-up resistors for use with switches and buttons.

MINI-IO has been designed to work with almost any software likely to be used for digital media playback. Reading data from a chain of MINI-IOs is very simple. Example projects are given in Max/MSP, Pure Data, Processing, Ableton Live, Kontakt, Qlab and Show Cue System. In fact, MINI-IO can be used with any MIDI- and Open Sound Control-compatible software or hardware.

MINI-IO provides accurate and stable 12-bit sensor values by automatically sampling in the background and either (1) averaging the most recent values to smooth the data or (2) storing only the peak values between read commands so that peaks/troughs are not missed at lower polling rates. Both schemes are user configurable and can be disabled if not required.

For those that want to customise MINI-IO, an ICSP connection is available for programming the on-board Microchip PIC16F1872 microcontroller with custom firmware. Pin assignments and oscillator configurations are detailed in the manual.

MINI-IO has been tested with all types of popular sensors including analog and digital ultrasonic proximity, infrared proximity, PIR, temperature, accelerometer, gyroscope, magnetometer and passive resistive sensors (pressure, magnetic switch, light).

Connection example:

Back to Blog