Frequently asked questions
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Q: What is a DAQ and what is it used for?
A: DAQ is the most typical acronym for "Data Acquisition Device". Data acquisition is the process of sampling signals that measure real world physical conditions and converting the resulting samples into digital numeric values that can be manipulated by a computer. Most DAQ devices also offer means to interact with the environment such as analog or digital outputs.
Q: How could I obtain a openDAQ?
A: You can acquire openDAQ directly buying it at this website. It's very easy! Items are paid by PayPal. Please, read our purchase information page for aditional info.
Q: How do I control openDAQ?
A: openDAQ is controlled via a serial port binary protocol. In the support page you will find the necessary documentation, and also some software utilities, like low level communication libraries for Python that will make it very easy for you to start using openDAQ. There are also available some software demos and sample programs that may help you to test the device functionalities.
Q: What is the best way to start using openDAQ?
Q: Can I use openDAQ in Linux? And in a Mac computer?
A: Sure. Just download the appropiate USB drivers for your computer. You can use the source code for openDAQ in Python or LabVIEW, with almost no modification, employing the corresponding interpreter for each platform. The compiled version of the sample applications, however, is only compatible for Windows.
Q: What is an analog input?
A: An analog input converts a voltage level into a digital value that can be stored and processed in a computer.
Q: Why would you want to measure voltages?
A: There are a multitude of sensors available which convert things like temperature, pressure, etc. into voltages.
Q: Then, what is an analog output?
A: Analog output converts digital values from a computer into a voltage level. This provides an adjustable output.
Q: What is a digital input?
A: A digital input provides a voltage thresholding operation. If the voltage is higher than some value, the computer will detect the digital input as high/set/1. If the voltage is lower than some value, the computer will detect the digital input as low/clear/0.
Q: And a digital output?
A: A digital output allows you to control a voltage with a computer. If the computer instructs the output to be high, the output will produce a voltage (5Volts). If the computer instructs the output to be low, it is connected to ground and produces no voltage.
Q: What is the counter input for?
A: Counter input automatically stores number of digital signal changes on port D5 (rising or falling edges). It is useful for taking measures with some kinds of sensors, like encoders, that produce a digital output signal.
Q: And the capture input?
A: Capture input permits measuring the time length of incoming digital signals.
Q: What is a PWM output?
A: PWM is the acronym for "pulse width modulation". It is a technique for getting analog results with digital means. It is based on a square wave signal, a signal switched between on (5V) and off (0V). This on-off pattern can simulate voltages in between full on (5 Volts) and off (0 Volts) by changing the portion of the time that signal spends high versus the time signal spends low. This relationship is called "duty cycle" and it is expressed in %.
Q: What is the Waveform Generator and what is it used for?
A: OpenDAQ has an unique feature which is the possibility to generate custom shape waveforms. The device uses its DAC output to reproduce a sequence of points at different voltages, allowing to generate signals in square, triangle, sine or any custom shape.
Q: Can you read an encoder with openDAQ?
A: Sure, in fact the standard firmware has features specifically designed to read quadrature incremental encoders, either rotative or linear.
Q: Is openDAQ compatible with Arduino?
A: You can program the firmware using Arduino IDE, using special hardware definitions and libraries. A specially adapted IDE can be downloaded from support page.
Q: May I modify the firmware of openDAQ?
A: Yes, indeed we encourage you to do so! The device is based on an AVR microcontroller, ATMEGA 644P. The source code was created using AVR-GCC, and it has been made compatible with the Arduino IDE. This makes it quite easy to modify. You can download the source code of openDAQ and instructions about how to modify Arduino IDE to work with it in the device manuals, in Support page.