Overview

The DataDuino data acquisition (DAQ) kit is designed to be robust and configurable but relatively simple. It is based upon the Arduino platform (using the Uno bootloader). It stores data to an SD card and uses a real time clock for accurate timestamping. The fastest resolution is 1 second sampling, up to 99999 second sampling.

Data acquisition is always useful to monitor a wide range of projects. Knowledge is power. With data, you can monitor your system, make changes and record how well they do and generally improve the things you are working on.

Data is stored onto an SD card. A real time clock is used to time-stamp the data and the output is a .csv file.

Sample Arduino code for a datalogger unit is provided here and can be built upon.

Details

This kit is designed as the data-logging 'backbone' you your project. You will need to include interface circuits for your sensors.

The DataDuino code is designed to read 1 x pulse sensor, up to 4 x 1-wire temperature sensors, 3 digital channels and 4 analogue channels.

This can all be changed within the DataDuino code using the Arduino IDE. This design is based upon an ATmega328 programmed with the Arduino bootloader. This makes it easy to configure and change and there are a huge amount of open libraries to use. This board (with an ATmega328) does not include the USB to serial converter (which would be on a standard Arduino), but I used an external USB to serial FTDI cable to program these boards. These cable are available at low cost and easily and are very useful.

The ATmega328 is interfaced to an SD card holder, along with very simple voltage level conversion. The ATmega IC works at 5V and the SD card works at 3V3, hence a 3V3 regulator and some potential divider resistor networks are required.

A real time clock is also used to time-stamp the data. This is a standard IC (PCF8563) which has a battery backup. It is a fully configurable PCB with an SD card holder and real time clock with battery backup. It also works as a Arduino for any other project.

As a basic unit, there are 5 digital data lines and 4 analogue data lines. The analogue lines can be converted into digital, if required. There are 4 additional digital lines which can also be used for data logging, but which mean slight loss of functionality.

The pin allocation is listed here.

More details

More sdetails including full schematics, sample Arduino code and full parts list are here.

Use Cases

This unit has been used for data-logging residential hot water temperatures and also for solar PV systems. Here is a DataDuino in a laser cut enclosure (sorry, not included, but email if you are interested):