An Arbitrary Waveform Generator (AWG) can be used to generate signals. Besides some standard signals, arbitrary signals can be generated. An arbitrary signal can be any previously measured signal or software generated data.
An Arbitrary Waveform Generator can be controlled with the AWG control window, which is shown in picture 1.
Picture 1: Generator screen. Click on the different areas to get more information.
The AWG control window contains a toolbar, for easy access to frequently used functions, and some control groups for signal properties. The toolbar and the control groups are described below.
The toolbar at the top of the window contains some buttons for easy access to frequently used functions. The function of the different buttons is described in the table below.
|Open||Open settings and/or arbitrary data|
|Save||Save settings and/or arbitrary data|
|Save as||Save settings and/or arbitrary data in a new file|
|Save and email||Save settings and/or arbitrary data and attach it to a new email|
|Reload||Reload previously opened or saved settings and/or arbitrary data|
|Help||Display help about the AWG|
The different signal types supported by the AWG can be selected with buttons. The signal that will be at the output of the generator, is displayed. By default, no arbitrary data is loaded into the AWG. As a result only an offset is generated when 'arbitrary' is chosen. See Arbitrary data for information about loading data.
The frequency can be adjusted with the range select buttons and the scroll bar. An exact frequency value can be entered after pressing the hotkey F or after double-clicking the frequency display. A button to set the frequency value to a power of ten (1, 10, 100, 1000, etc.), based on the selected frequency range, is also available. The actual value is shown on the display.
By default the generator is working in DDS mode and the signal frequency is displayed. This is the frequency at which the displayed signal will be repeated. It is also possible to change the sampling frequency of the AWG directly by checking the sample frequency radio button. The generator is then working in linear mode.
In linear mode, all samples in memory are output sequentially, without skipping samples. In DDS mode some samples may be skipped to make it possible to generate the desired output frequency.
The minimum and maximum frequency will depend on the instrument.
|Instrument||Signal frequency||Sample frequency|
|Handyscope HS5 1||238 nHz to 30 MHz||28 mHz to 240 MHz|
|TiePieSCOPE HS805||0.1 Hz to 20 MHz||0.1 Hz to 200 MHz|
|Handyscope HS3||0.1 Hz to 2 MHz||0.1 Hz to 50 MHz|
The symmetry can be adjusted with the scroll bar. An exact symmetry value can be entered after pressing the hotkey S or after double-clicking the symmetry display. A button to set the symmetry value to Mid value (50%) is also available. The actual value is shown on the display.
The symmetry range is 0% to 100%.
The amplitude can be adjusted with the scroll bar. An exact amplitude value can be entered after pressing the hotkey A or after double-clicking the amplitude display. The actual value is shown on the display.
The minimum and maximum amplitude will depend on the instrument.
The offset can be adjusted with the scroll bar. An exact offset value can be entered after pressing the hotkey O or after double-clicking the offset display. A button to set the offset value zero is also available. The actual value is shown on the display.
The minimum and maximum offset will depend on the instrument.
The two buttons in the output group can be used to turn the output on or off, and to start or stop the signal.
Turn AWG on/off.
Start/stop AWG signal output.
By default, the signal will output continuously, but it is also possible to perform a burst of a certain number of periods of the signal. To perform a burst, check the "Burst" radio button and select or type the number of periods in the combo box. After pressing "Start" the burst will be generated. The TiePieSCOPE HS805 only supports burst mode when signal type Arbitrary is selected and the generator operates in linear mode (frequency controls set the sample frequency).
The AWG in the Handyscope HS3 can also be started using an external trigger signal, instead of using the "Start" button. This signal has to be applied to the extension connector at the rear of the instrument. Refer to the instrument manual for detailed information on the extension connector. External triggering is selected through the popup menu that is opened by right clicking the AWG in the object tree.
All settings and arbitrary data of the AWG can be saved in setfiles with the "Save" and "Save as" buttons on the toolbar. In picture 1 for example, setfile Sin3.TPS is loaded, which contains an arbitrary signal (sine^3).
Setfiles can be loaded with the "Load" toolbar button, or by dragging a setfile onto the AWG control window.
Besides some standard signals, the Arbitrary Waveform Generator (AWG) can output arbitrary data. There are different ways of loading such data into the generator. Data can be loaded directly from an open source in the software, or from a file.
Data of every source in the Multi Channel software can be loaded directly into an AWG. This means that measured data, but also processed or generated data can be put into the AWG. There are two ways to do this. One way is to drag the source onto the AWG in the object tree. The other way to get the data of a source is to drag the source onto a AWG control window.
Depending on the AWG and the data size, data may be resampled during loading.
Besides loading data from a source, it can also be loaded from a file. Currently, loading data from TiePie engineering TPS files, TiePie engineering WinSoft DAT files and from Wave audio files is supported.
From a TiePie engineering TPS file, data can be read from each AWG or Source chunk in the file.
From a TiePie engineering WinSoft DAT file, data will be read from the first channel in the file.
Data from Wave audio files can also be read into the AWG. If more than 1 channel is available in the file, only the first channel will be read. All uncompressed Wave audio files with a resolution of 8, 16, 32 or 64 bit are supported.
Depending on the AWG and the data size, data may be resampled during loading.
You can create ASCII files that look like WinSoft DAT files to be able to load your data into the function generator's memory. Because the function generator only loads the data of channel 1, only the third column is needed in the file. You may create a file with .DAT extension and contents looking like this:
[SCOPE] ,,0 ,,1 ,,2.5 ,,-4
This file contains 4 lines of voltage values, but the file may contain any number of data lines. Depending on the AWG and the data size, data may be resampled during loading.
When loading data into an AWG, it is possible that the AWG does not support the data size of the loaded data. This can happen for example when the data is to big to fit into the memory of the AWG. The TiePieSCOPE HS805 and Handyscope HS3 have another limitation: the data size must be a power of two (2, 4 , 8, 16, ..., 262144).
When it is not possible to set the data size of the AWG to the data's size, the data will be stretched or shrunken to fit exactly into the possible data size that is closest to the requested data size.
The AWG can be controlled with several hotkeys, see the hotkey page for a complete list.
The AWG in the Handyscope HS3 has three trigger output signals which are internally connected to the trigger system of the oscilloscope part of the instrument. In the oscilloscope they can be used as trigger source, to provide an exact synchronization between signal generation and measuring. The available trigger signals are: