Network Data Logger

USER MANUAL

mgr inż. Mieczysław Rekowski

mgr inż. Jerzy Suchcicki

mgr inż. Andrzej Skrzyński

W A R S Z A W A 2 0 0 7

Table of Contents

1 INTRODUCTION.

1.1 Exterior view.

1.1.1 The front panel.

1.1.2 Rear Panel.

2 OPERATION.

2.1 Preparation of registration.

2.2 Running registration.

2.3 Data processing after registration.

3 OPERATING THE RECORDER NDL.

3.1 Start and stop recording.

3.2 Setting up the recorder

3.3 Handling clock.

3.4 Notices.

4 RECORDER SOFTWARE.

4.1 Preparation of registration - NdlSet program.

4.2 Checking of registration - Ndl program.

4.2.1 Signal window.

4.2.2 The window of the spectrum.

4.2.3 Filter window.

1. Introduction

Network Data Logger (NDL) is used to record the electrical signals coming from the detectors of physical phenomena. The device is equipped with a system to communicate with a computer network, allowing remote control of the recorder and the transmission of results. The compact, encapsulated design impact-resistant closed housing predisposes the instrument to be used in geophysical measurements, especially in the difficult conditions in the work field and unmanned stations. Battery-powered (external battery) allows the use of NDL away from human settlements and access to electricity.

The main features of the device include:

- Record data on USB Compact Flash,

- Sigma-delta converter with a resolution of 24 bit

- The use of digital signal processor DSP56002,

- The use of processor firny Atmel AVR family,

- Digital signal filtering FIR filters and IIR

- Cooperation with external Universal Time (GPS or DCF)

- Co-operation with the local internet network

- Supports TCP / IP and FTP

- Auto-tune their clock to the time from the GPS or DCF


1.1. Exterior view

1.1.1  The front panel


Figure 1 NDL recorder front panel.

1.1.2. The rear panel


Figure 2 NDL recorder rear panel.

On the rear panel are:

–  INPUT - DB-25 socket for connecting input signals

–  GPS - DB-9 connector for connecting DCF or GPS

–  RS-232 DB-9 socket for connecting eg magnetometer PMP-8

–  NET - RJ-45 connector to connect recorder to a local area network

–  12VDC - SzP-3 socket for power supply

2. Service.

In the process of record keeping by recorder can be divided into three stages:

–  preparation of registration

–  running registration

–  data processing after registration

2.1. Preparation of registration

Preparation of registration in terms of the recorder is mainly formatted Compact Flash (CF).

Before first use CF memory in the recorder it is needed:

connect the CF memory to the computer (USB reader or PCMCIA)

format the CF (FAT-16 or FAT-32)

create a directory called DATA

run the NdlSet program and do the following commands:

a / the drop-down list, select the correct drive

b / from the File menu choose New.

The drop-down list contains all logical drives currently installed in your computer and make sure that the selected drive is correct (CF card).

Upon completion of all operations on the CF card in the root directory will be created the file "Ndl.cfg". Description NdlSet program is contained in section 4.1 of this manual.

2.2. Running registration

Put the prepared CF card to the recorder NDL. After powering the unit is ready for operation, by repeatedly pressing the button [HOME], [ENTER], [ENTER] key, start recording. If you press the [HOME] [ENTER] [ENTER] to stop recording. Stop recording the [HOME] [ENTER] [ENTER] to save the file "Ndl.cfg" additional information relevant to the format of the data, and course registration. DO NOT stop REGISTRATION BY TURN OFF POWER. In case of power failure (stop recording), copy the previously saved data and prepare for. point. 2.1 user, the CF card to register.

The data are stored in the automatically generated files NDL_nnnn.dat, where nnnn is a sequence number file, in a directory named DATA. The default size of the configuration file is included in the Ndl.cfg file / see below /. This allows continuous recording and copying files from the recorder NDL FTP by network to a computer.

Control of the registration / view / allows program Ndl. Description Ndl program is contained in section 4.2 of this manual.

2.3  Data processing after registration..

The data files are stored on the CF card in the DATA directory. The file names are created on the basis of time (CLOCK DSP) in the following format: YMDHmmss.nrr,
where:
· Y - the yearcode
· M - the month code
· D - the day code
· H - the time Code
· Mm - minutes in decimal code
· Ss - seconds in decimal code
· N - recorder code (n - NDL, p - PMP-8)
· Rr - serial number of the recorder in decimal code
Table od codes
Code / Year / Month / Day / Hour
0 / 2000 / 0
1 / 2001 / Jan / 1 / 1
2 / 2002 / Feb / 2 / 2
3 / 2003 / Mar / 3 / 3
4 / 2004 / Apr / 4 / 4
5 / 2005 / May / 5 / 5
6 / 2006 / Jun / 6 / 6
7 / 2007 / Jul / 7 / 7
8 / 2008 / Aug / 8 / 8
9 / 2009 / Sep / 9 / 9
a / 2010 / Oct / 10 / 10
b / 2011 / Nov / 11 / 11
c / 2012 / Dec / 12 / 12
d / 2013 / 13 / 13
e / 2014 / 14 / 14
f / 2015 / 15 / 15
g / 2016 / 16 / 16
h / 2017 / 17 / 17
i / 2018 / 18 / 18
j / 2019 / 19 / 19
k / 2020 / 20 / 20
l / 2021 / 21 / 21
m / 2022 / 22 / 22
n / 2023 / 23 / 23
o / 2024 / 24
p / 2025 / 25
q / 2026 / 26
r / 2027 / 27
s / 2028 / 28
t / 2029 / 29
u / 2030 / 30
v / 2031 / 31

There are two ways to transfer data from the device to the computer NDL.

1.  Once registration is complete, turn off the power, remove the CF card from the device and copy the data from the card using a CF reader.

2.  Connect the recorder to a local area network or directly to the network adapter in your computer using a suitable cable and copy the data from the recorder by FTP. The IP address of recorder is set during the preparation of the CF card by the program NdlSet / see 4.1. /.


Address and password for the recorder server FTP:

username: - ftp_rw

password: - *****

Processing depends on the type and purpose of the experiment carried. Supplied with recorder the FdlSee program, allows you to view on a computer screen recorded signals.

Description of the FdlSee program is contained in a separate step instructions.

3. OPERATING THE RECORDER NDL

On the front panel there are buttons for programming the recorder work.

[HOME] button - from which we start select specific functions of the recorder.

Its meaning is always the same - back to the beginning.

[PREV] [NEXT] - buttons to select the previous or next function or value

of the list.

[ENTER] - confirm the selection and move to the next function.

When you press the [HOME] and [PREV] and [NEXT], we can choose:

- start and stop recording / default function /,

- recorder configuration,

- check and set the time.

3.1. Start and stop recording

Pressing [HOME] [ENTER] [ENTER] causes start or stop of the recording (depending on the state of recorder).

3.2. Setting up the recorder

After powering, the recorder reads from disk initial configuration (see the description of the FdlSet). Pressing the [HOME] [NEXT] [ENTER] and subsequently {[NEXT] ....} displays each recorder configuration parameters in the following order:

- number of channels,

- sampling,

- type low-pass filter,

- high-pass filter time constant,

When we display the parameter you can by pressing [ENTER] change the value. The [PREV] and [NEXT] key are used to choose the value.

IIR filter time constant is dependent on the selected sampling period is equal to the product of the IIR filter shown on the display, and the sampling period.

3.3. Handling clock.

The recorder NDL are three clocks / timers:

NUT CLOCK - system clock NUT / OS - set manually or automatically at power on, from RTC. Used by the system to determine the time of setting the files.

RTC CLOCK - the system clock with battery backup, manually set from DSP, you need only to start the system clock. This requires setting the running out, replacing the lithium battery or a long break in recorder work.

DSP CLOCK - DSP ​​clock manually set from the clock NUT and automatically from the GPS or DCF. synchronized with external GPS receiver, or DCF. It is used for precise time recorded signals and the sampling period. With proper GPS reception or DCF provides high accuracy sampling, i.e. the same number of samples of the A / D in each period of registration. If there is neither GPS nor DCF, it can be set from clock of the system.

Press the [HOME] [NEXT] [NEXT] [ENTER] to display the clock time. Use the [PREV] and [NEXT] to select the clock, and once selected, press the [ENTER] key to manually setting it to another clock.

3.4. Notes

Averaging FIR - filter which is calculated from the arithmetic mean value of the signal, sampled at 12,800 samples per second. Not strong enough to suppress the signal frequencies greater than half of the sampling frequency. If the input signal has a high frequencies and it is selected Averaging option FIR or FIR OFF it will produce aliasing phenomenon.

MINIMUM FIR and LINEAR FIR - antyaliasing digital FIR filters (filter finite impulse response). The filtered signal has a flat frequency response amplitude up to 0.4 of sampling frequency, and for frequencies greater than half the sampling filter attenuation is greater than 90dB.


4. RECORDER SOFTWARE

A set of programs designed to work with the registrar FDL working in Windows:

NdlSet - a program for preparing memory cards

ADRs - a program to control the recorder operation

FdlSee - viewer program

4.1 Preparation of registration - NdlSet program.

Figure 3 The main window of the NdlSet program

Figure 3 shows a view of the main window of the NdlSet program used to prepare the memory card recorder NDL. The drop-down list at the top of the left pane contains a list of all the disks in the system. The first step is to select the proper drive operations to which they relate.

The main window contains four tabs in the bottom of the parameters to configure the recorder.

ADC tab contains buttons to configure the registration (number of channels, sampling frequency in the channel, type FIR low-pass filter and a high-pass filter time constant for IIR).

Files tab is used to organize the registration, you can select the size of files created and allows recording buffer. This registration mode causes the assumed number of files meeting or exceeding the established time of recording the oldest files are deleted. The zero value of the parameter Max Files and Max Time to stop recording when the media becomes full. Registration buffer can be controlled by parameters Max Files and Max Time. Checking the Auto Start will automatically start recording when you turn on or power interruption.

Net tab contains three edit fields that are used to configure the network connection DVR IP address, mask and gate number.

Pass tab is used to authenticate the network connection. Includes four edit fields:

· Tcp Ro Pass - a password to control the DVR through the DVR NDL

· Tcp Rw Pass - a password to control and configure the DVR recorder with NDL

· FTP Ro Pass - ftp password read-only

· FTP Rw Pass - ftp password to read, write and erase

Selected parameters are stored on the button after approval Write and read in by the recorder after it starts.

In case of a bad disk selection displays the following message:

which protects the drives installed in your computer against unauthorized program.

The commands in the File menu:

New - Creates the formatted media file in the root directory Ndl.cfg

This file contains the configuration of the the recorder NDL.

Open - to open the file Ndl.cfg displays its parameters.

Clear - This operation resets the contents of the file Ndl.cfg. In this case,

also delete all the files in the DATA directory.

All these operations update the information at the bottom of the left pane:

Start sector - the number of the first sector of a logical file Ndl.dat

Sectors in file - the number of all sectors in the file,

Free sectors - the number of free sectors in the file.

Based on the number of free sectors and set parameters registration / number of channels and sample rate / program calculates the approximate recording time on a carrier

and displays it at the bottom of the panel in the following format:

xxx.hh: mm: ss

where:

xxx - number of days