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TEST-SIGNAl GENERATORS FOR mINDSET
mS-1000 ElECTROENCEPHAlOGRAPH
wITH DATA ACquISITION SYSTEm FOR lINux OS
s
ławoMir
k
otyra
, g
rzegorz
M. w
óJcik
Institute of Computer Science, Maria Curie-Sklodowska University 
Marii Curie-Skłodowskiej Sq. 1, 20-031 Lublin, Poland
Abstract:
The paper presents a hardware and software solution giving methods of communication and the construction of the 
artiicial EEG patients. The software is designed for the Mindset MS-1000 EEG 16-channel device, manufactured by Nolan 
Computer Systems. The modular analysing system for Linux OS is presented. In addition, to testify the calibration of the device 
– the artiicial patient has been designed and constructed together with appropriate hardware-software generators. 
Introduction
In the Division of Complex Systems and Neurodynamics of 
Computer Science Institute of Maria Curie-Skłodowska Uni
-
versity a software for data acquisition and processing is being 
developed [1]. The software is designed for the Mindset MS-
Fig. 1.
Example of EEG examination set
1000 EEG device, manufactured by Nolan Computer Systems. 
This device contains a 16-channel analog ampliier, a 16-bit 
analog-to-digital converter and a gathered data transmission 
trace. 

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Ima
ge
Pr
ocessing
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Test-signal generators for Mindset MS-1000 electroencephalograph…
The device control and data interchange is operated by 
a SCSI interface [2][3]. An appropriate SCSI commands set 
makes it possible to control the sampling rate value (64, 128, 
256, 512 or 1024 samples per second) and to begin and inish 
the process of data sampling [4].
The goal and general idea
The goal is to develop (under Linux OS) a complete examination 
system for the versatile analysis and visualization of EEG signals.
The idea of the project is to build a modular system, where 
individual modules are as much independent as possible, with 
a wide choice of active modules and an ordering option. A pipeline 
was chosen as an inter-process communication background.
A calibrator is an optional equipment for the EEG Mindset 
MS-1000 device. It is a sinusoidal, 16 Hz, 50 μv signal oscillator. 
Signal parameters of this oscillator are good. The deviations are: 
frequency below 1%, magnitude below 2% and harmonics factor 
below 1%. The main purpose of this calibrator is to determine 
scaling factors for data errors corrections – due to factors such 
as electronic components tolerance, small errors may occur in 
the process of data gathering [5].
Realisation: EEG test signal 
oscillators
At the irst stage, a daemon program was developed. The role 
of the daemon is to control the Mindset MS-1000 EEG device 
and to receive data from it. An oscilloscope program was also 
developed to show the gathered data on the screen [6]. At this 
stage the calibrator was used as a signal oscillator.
Fig. 2.
Two seconds of calibrator signal (512sps)
One of the next stages of the system development will be the 
frequency spectrum analysis of the signal with Fourier transform 
[7]. For a more reliable testing of this system module, a more 
advanced signal oscillator is necessary.
It is possible to buy signal oscillators for the testing of the 
EEG equipment (sometimes called 
artiicial patient
), however, 
they usually contain only one function oscillator that generates 
a single sinusoidal, rectangular or triangular signal with variable 
frequency.
Rectangular and triangular waves are rich in odds harmonics, 
and this feature makes the testing of frequency spectrum analysis 
possible. We exactly know what the expected result is, because 
the waveforms are described in the form of the following formulas:
–
for a symmetric rectangular waveform [8]:
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