Measure.exe for DrDAQ

 

DrDAQ is a device of Pico Technology to be connected to a PC via USB for measurements of voltages, resistance, pH values, light brightness, sound and temperature. The software that comes with this device is able to measure, but not to store big amounts of data.

 

Measure.exe is a program to measure data, do an analysis during the measurement (with alarm function) and store the results with high velocity. Measure.exe does not (yet) support the output channels of the device. Below you will find a more detailed description of the program, which is a copy of the manual.

 

 Download measure.zip (© see below, note that is dangerous to use programs of others!)

 

 

 

Sample measurement result:

 

 

Table of contents

Measure.exe for DrDAQ

1      Installation

1.1       Package content

1.2       Measure.exe

1.3       Run the program

1.4       Quit the program

1.5       Remarks

1.5.1        Windows versions

1.5.2        CPU usage

1.6       CheckRD

2      How to Use

2.1       Test single channel

2.2       Get all channels

2.3       Start stream

2.3.1        Configuration file

2.3.2        Result files

2.3.3        The dialog window

3      Exclusion of liability

4      Copyright

5      Support

 

 

 

Installation

Package content

The zip file contains:

 

 

Measure_XP.exe

Program to measure with DrDAQ for Windows XP (and probably all later Windows versions)

Measure.exe

Program to measure with DrDAQ for Windows 8 (and probably Vista and Windows 7, but NOT for XP)

CheckRD.exe

Program to analyze raw data

Measure_scope.mcf

Sample configuration file to measure AC voltage with high sample rate (10 kSamples per second) and save important results to file

Measure_Temperature.mcf

Sample configuration file to measure and save Temperature data for a long period

Measure_light_frequency.mcf

Sample configuration file to measure light brightness with high sample rate (10 kSamples per second), calculate frequency without saving data.

This may be a good sample to start with, as you do not need any settings.

Measure_cfg_file_format.mcf

Explains the format and entries of the configuration files.

Measure_en.doc

English manual

 

 

Note: the .mcf (measure configuration) files are pure text files.

 

Measure.exe

The program measure.exe is written with the Microsoft Visual C++ version 6.0 running under Windows XP. It uses the MFC which is linked statically to the program. Therefore, the only DLL, that is required, is UsbDrDaq.dll. This is installed when you install the software of picotech for DrDAQ. Measure.exe was developed with version 1.0.0.93 of this DLL.

 

There is another version of measure.exe, compiled with Visual Studio 2012. This version should run on Windows 7 and Windows 8, maybe on Vista, too. You can distinguish the programs after opening the About-dialog, that shows the compiler version. The main difference is, that the XP-version does not support file sizes larger than 2 GB.

 

Run the program

To run measure.exe, just copy it to any directory and start it. If you start it without any parameter, the program will try to connect to the DrDAQ (actually, only 1 device is supported) and display the result in the top line of the window. If DrDAQ Status equals 0, the program is ready to run. Else you should find the error, which may be one of the following incomplete list:

1.      UsbDrDaq.dll is missing (or not found, as it is in a wrong directory).

2.      Another program uses the device.

3.      measure.exe was not closed completely. (This may happen, if the program crashes, or if you quit the program before stopping the measurement.) Look for measure.exe using the Task Manager and kill all running instances of measure.exe before starting a new one.

4.      If the steps above do not work, repeat it and unplug the device from the USB port. Then connect it again and run the program.

 

If  DrDAQ was connected successfully, you may click Get all channels to read all input channels of the device (see below).

 

If you find the program useful, you may use an predefined or self created configuration file as the first (and only) command line parameter to run the program with your desired settings (see below).

Quit the program

Clicking the button OK quits the program is no measurement is running. Else a message box is print.

Clicking the close x right besides the title bar will quit the program in any case. You should use it only an an emergency case, as data may be lost and the program may not be shutdown safely.

Remarks

Windows versions

measure.exe is a program for Windows XP, but should run in newer Windows versions, too. I use it in Windows 8 without problems. However, when I tested it using the compatibility mode Windows XP SP 3, the program run, but failed to write data to a RAM-drive that was created with the tool ImDisk.

CPU usage

If you run the program using the streaming mode, you will find that the program uses one CPU completely (100%). This is caused by UsbDrDaq.dll of picotech and I cannot change this behavior.

 

If you have a computer with more than 1 CPUs, the program will use more than 1 CPU, as it is multithreaded. Additionally to the (mostly 2) threads within UsbDrDaq.dll measure.exe has, besides its main thread, 2 additional threads, if you run the streaming mode. One (with enlarged priority) collects the data and writes it into a buffer. This needs only few CPU time. The second reads the data from the buffer and does all calculations other actions you have specified in the configuration file. How much CPU time is needed for this, depends on the amount of calculations, which depends on the number of data to measure per time interval and also on the number of calculations, which you have defined in the configuration file for each measured value. Also, this CPU usage is much larger for the debug version of the program as for the release version.

 

Streaming with full velocity and online calculations are possible only with the release version running on a modern PC with at least 2 CPUs.

 

If you store the data to file, this may, firstly, block the program, if the writing velocity to the disk as slower than the data rate produced by the program. Secondly, the program can be hindered by high access times to the disk. Both problems can be solved by writing data to a RAM drive. (ImDisk is a free and stable tool for all Windows versions.) The data is written to file using a TAB separated text format. This needs a lot of space on the disk, but makes the data insertion into Excel or similar programs very easy. Therefore I store the big files on a RAM drive and save a zipped version on the hard drive, if I do not want to loose the data. The size of the zipped file is less than 10% of the original file.

CheckRD

CheckRD.exe is a helper program for Windows (XP and later, 32 bit, you do not need any DLL’s, as it is linked static) that works only with raw data files. It can analyze some aspects of the collected raw data. After starting the program without parameters it will print the usage instructions.

How to Use

 

Test single channel

The purpose of this measurement is to test how fast the function UsbDrDaqGetSingle of UsbDrDaq.DLL works. After clicking the button Test single channel the program fetches single values with maximum speed with only three parameters as input:

1.      The measurement is performed for the first channel checkbox that is selected. If none is selected, channel 1 (External 1) is used.

2.      Duration [seconds]: This tells, how long the measurement should last.

3.      Max. delay [microseconds]: The measurement counts how many of the function calls need more this time, and how many less. A message box will show the result when the measurement is finished. It looks like this:

 

 

Also, this message box asks you whether you want to save the data. If you click yes, data is appended to the file Measure_single_test.txt. The timestamp (column 1) is the number of seconds between starting the measurement and starting the function to get a single measurement value (column 2).

 

This test method is not multithreaded. Therefore you cannot use the dialog windows as long the measurement is running!

 

The following picture shows a typical result. Most measurements need between 12.5 and 15 milliseconds. But a few need more than 50 milliseconds. Probably this is caused by interrupts of the Windows 8 operating system. This shows, that a time resolution of about 100 milliseconds is possible with the function UsbDrDaqGetSingle. For a better resolution the streaming function must be used. The result is very similar for all channels which I have tested: Ext1, Ext2, Ext3, scope, light, temperature, sound wave, sound level. The external channels show a small, but significant number of measurements with duration of 16 and 17 milliseconds and the average duration is 12.785 compared to 12.755 for the other channels. The minimum duration for all channels was 12.300 milliseconds, the maximum 66 ms.

 

 

Get all channels

Purpose: Read all channels and print values to screen and file with a period larger than 100 ms.

 

This measurement uses as input:

 

The parameters are described in the chapter for streaming measurements.

 

After clicking the button Get all channels the program reads all channels (using the slow function UsbDrDaqGetSingle) with the specified period. (The program uses a minimum periods of 100 ms.) The result is displayed in the message listbox always, but writing to file depends on your settings in the dialog window.

 

This function is good for:

1.      Quickly checking actual values of all ports, e.g. for testing a proper connection of the devices before starting a stream.

2.      Long duration measurements with adjustable period. (No alarm function is implemented.)

 

Start stream

Purpose: Collect and analyze data with a rate up to 100,000 per second.

 

Configuration file

Usually, for streaming you will start the program with a configuration file as the first and only command line parameter. You can do this by dragging the configuration file and dropping it onto the program file measure.exe.

 

The name of the configuration file is free. It is a simple text file which can be modified using any text editor. It is NOT possible to save the configuration of the dialog to a file, as there are many entries in the file which are not shown in the dialog. Some entries of the file match the input parameters of the dialog and will be entered into the dialog when starting the program.

 

The meaning of the entries in the file is described in the sample file. Besides some common entries you can define channels for either measuring (input channels of the device) or just for calculations using the values of other channels.

Result files

Depending on the settings within the configuration file the results will be saved completely or partially to files. Using the maximum speed, I saw files increasing to 1 GB within 1 hour. Data is saved in text format, separated by TAB characters. So you can easily copy data to Excel or other programs for analyzing. The disadvantage of the text format is the big file size. You may consider to store the files using a zip program.

 

If you have a slow disk, it may disable the measurements, if data cannot be written as quick as they are produced. Using a RAM disk (e.g. ImDisk is free and good.) can solve this problem. A good method may be first to store the data to the RAM disk and to save it as a compressed file to a HDD after the measurement.

 

The result files which are defined in the configuration file are flushed after writing each line. This ensures that you have valid data even if the program crashes. The disadvantage is, that this method is not the best for HDDs, as this flushing needs time. For RAM disks, this does not matter. (The raw data files are opened at measurement start and closed when stopping the measurement. Here it is possible to loose data in case of program crashes.)

 

If the size of the result files which are defined in the configuration file exceeds 2e9 Bytes after writing one data block, it is renamed by appending the actual date and time to the filename. This avoids errors with files becoming too big.

The dialog window

The title bar shows the string specified in the configuration file. The same is valid for the checkboxes of the channels, the jump values below the checkboxes, the data request interval and the interval between 2 measurements.

 

Line 1 (DrDAQ Status) shows the status of the device, the first field is the status value, which is 0, if everything works well. The second field displays a message with some more information about the device.

 

Line 2 contains the measurement status as number and text.

 

Line 3 shows the progress of the measurement thread, that collects the data from the device. The first field shows the number of data points got so far. The second field shows the time since starting the measurement (only for streaming). The third field shows a text message.

 

Line 4 shows the progress of the analysis thread, which works up the collected data. The first field shows the number of data points worked up. You can compare this number with that of a line above to see, whether your computer is able to work up data in time. If there is an increasing delay you need a faster computer or you must reduce the measurement rate or the number of calculation channels.

 

Line 5 contains a checkbox for each channel. If the channel is set to measure in the configuration file, the checkbox will be selected when loading the configuration file. You can manually change the entries, but if you unselect a checkbox which is needed for any calculation channel, the result is unpredictable.

 

Line 6 contains a field for the jump value for each channel. If defined in the configuration file, it is set to this value, else it is 99999 and no jumps are reported as the measured values range from -32768 to 32676. During streaming measurements a jump is reported, if the absolute difference between two consecutive values is larger than the jump value. (To see the message you must set the debug level to at least 2.)

 

On the left side below line 6 are 10 fields for the results. The first shows the time since starting the measurement. If the thread for working up the measured data is late, this time differs from the time at which the displayed data had been measured! 9 other fields are filled as specified in the configuration file.

 

The right side shows parameters for the measurement and for the output:

 

Below the results and parameters there is the message list. New messages are appended at the bottom. You might not see the most recent messages, as there is no automatic scrolling. So you are able to read all messages one after the other by scrolling yourself. Only when running Get all channels there is automatic scrolling to show you always the most recent values. If the list contains more than 10000 entries, it is emptied.

 

At the bottom of the dialog you can find following buttons:

-         OK: Quit the program. Before quitting you should stop the measurement. Else you could have troubles to start a new one.

 

Exclusion of liability

The user of the programs is alone responsible for the outcome, I herewith deny any liability of my person or company! These macros can contain programming errors. Principally, the programs may display wrong results and even damage your computer or connected devices.

 

DISCLAIMER OF WARRANTY.

THE SOFTWARE IS PROVIDED AS IS WITHOUT WARRANTY OF ANY KIND. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, EDV ABMAYR FURTHER DISCLAIMS ALL WARRANTIES, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND NONINFRINGEMENT. THE ENTIRE RISK ARISING OUT OF THE USE OR PERFORMANCE OF THE PRODUCT AND DOCUMENTATION REMAINS WITH RECIPIENT. TO THE MAXIMUM EXTENT PERMITTED BY APPLICABLE LAW, IN NO EVENT SHALL EDV ABMAYR BE LIABLE FOR ANY CONSEQUENTIAL, INCIDENTAL, DIRECT, INDIRECT, SPECIAL, PUNITIVE, OR OTHER DAMAGES WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS OF BUSINESS PROFITS, BUSINESS INTERRUPTION, LOSS OF BUSINESS INFORMATION, OR OTHER PECUNIARY LOSS) ARISING OUT OF THIS AGREEMENT OR THE USE OF OR INABILITY TO USE THE PRODUCT, EVEN IF EDV ABMAYR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

 

Copyright

These programs may be copied, used and modified freely for private and other not commercial purpose. You may give them or parts of them freely to others only together with the information about the author, the exclusion of liability and the copyright. These programs or parts of them must not be sold and they must not be used for commercial purpose without permission of the author. For this you need a license (contact) after testing the programs for your purpose for a maximum of 2 weeks.

 

Support

Please understand that I cannot give free support for a free program. If you need help or improvements of the program  contact me and tell me you wishes to get an offer for my help.

 

 

 

 

First published: July 13th, 2013

Last change: July 16th, 2013

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