Loading User Files -
» You have the option of loading your own custom waveform files. Before loading a custom file, you should first load the Default file so that you will have some default values for the built-in waveform parameters.
» You can access the User-Defined Waveforms section by typing 256 into the
Waveform Code box.
» An User Defined Section will replace the Linear Chirp section. You can then click on Open to bring up Open User
Defined Waveform File window.
» Once the Open User Defined Waveform File window pops up you just need to select a custom user file. Note that
your custom files should have an .uwf extension. Select your file and click on Open.
» Once the file has been loaded the Data Length should have adjusted automatically to correspond with the number of frequencies
detected in the file. You can then click on "Download" and start the custom waveform.
» If you change your .uwf file in a text editor, you do not need to re-open the file. Simply click on "Reload" and the file will be
updated in the application and automatically downloaded to the DSM.
Creating User Files
The user waveform files must have a .uwf extension and should be in ASCII encoding. You can create these with a typical text editor such as Notepad that is included with Windows. The file is basically a list of frequencies that you want to chirp separated by newlines. The frequencies are either specified in frequency word or absolute frequency. For absolute frequencies, the frequencies can be specified in either decimal or hexadecimal. The user waveform files must have two descriptors on the top of the file. An example of the descriptors is shown below:
#type = 1
#hex = 1
The #type specifies the type of frequency to be entered as well as if control bit words will be used. "1" is for frequency word without control bit words and "2" is for absolute frequency without control bit words. "5" is for frequency word with control bit words and "6" is for absolute frequency without control bit words. The four types are summarized in the table below. For frequency word, make sure that you do the right calculations and take the input clock frequency into consideration to get the desired output frequency. For absolute frequency, some of the frequencies might be rounded off to the nearest converted frequency word.
| #type | Description |
| 1 | Frequency words without control bit words |
| 2 | Absolute frequencies without control bit words |
| 5 | Frequency words with control bit words |
| 6 | Absolute frequencies with control bit words |
The control bit words are basically two control bits that represent phase reset and marker. Bit 0 or the first LSB controls whether the marker is high or low while bit 1 or the second LSB controls the phase reset. For the phase reset bit, "0" turns phase reset off while "1" turns phase reset is on. For the marker bit, "0" turns marker low while "1" turns marker high. Here is a table showing the possible combinations of the control bit:
| Dec / Hex | Binary | Phase Reset | Marker |
| 0 / 0x0 | 00 | Off | Low |
| 1 / 0x1 | 01 | Off | High |
| 2 / 0x2 | 10 | On | Low |
| 3 / 0x3 | 11 | On | High |
If you have chosen to use the control bit words, you do not need to specify control bit word for every frequency data point. The default setting if you do not set a frequency control word is "0" meaning no phase reset and marker low. So you only need to specify the data points where you do want phase reset or marker.
The #hex specifies if the absolute frequency will be specified in decimal or hexidecimal. "0" is for decimal and "1" is for hexadecimal. Note that if you choose the type to be frequency word then you can ONLY use hexadecimal.
Please note that the control bit words format is also controlled by the #hex setting. If #hex is set to decimal then the control bit words should also be in decimal and if #hex is set to hexadecimal then the control bit words should also be in hexadecimal.
Example User Files
» Frequency Word Demo Chirp
This file is a replication of the Demo waveform that is displayed everytime the DSM is turned on. It is expressed in hexadecimal frequency word as described in the top two lines.
» Decimal Linear Chirp
This file does linear chirping by specifying the absolute frequencies in decimal. When the decimal frequencies are fed into the software, they will be rounded to the closest frequency word.
» Non-Linear Frequency Word Chirp
This file uses frequency words in hexadecimal. This waveform shows non-linear chirping with uneven spacing between every other frequency.
» Exponential Frequency Word Chirp
This file also uses frequency words in hexadecimal. This waveform demonstrates exponential chirping doubling the frequency every time.
» Non-Linear Frequency Word Chirp with Control Bit Words
This file also uses frequency words in hexadecimal but this time uses the control bit words to control phase reset and markers.