You can use the Sound Exporter module along with Signal Generator module to make a fully functional PC sound card based signal generator. The SoundExp module can generate real signals using sound card.

You can also use other modules to generate the waveform data. For example, you can load the data from binary or text files.

Open the SndGen.dsp project in DspSee to have a fully functional PC based signal generator. Click to download DspSee dsp software.

Example using Schematic Editor

The above example can be used to make a pc based signal generator (synthesizer). As you can see, the schematic based approach is very simple. Just add the desired modules from the module list, and connect them with the wires the way you want.

Double click on the SigGen symbol to open its settings. Set the frequency to 1K, sample rate to 8K, peak-peak to 2 and record length to 10K.

That's it, you are ready for the fun. Just click on the Run button on the toolbar to generate the sound.

Example using Script

You can also write a script to achieve the same objective. Below is a description of the PCScope.dsp project file. Feel free to change it to try different things.

File starts ->

//SndGen.dsp //Copyright www.aubraux.com //DspSee sample file. Shows generation of real signals with SoundExp module. //Requires SoundExp, SigGen and Plot modules.
//Modulating Signal Generator
load wm="SigGen"	//Loads the SigGen module. This module can generate waveforms of different shapes.
wm.type="sine"	//Sets signal type as sine
wm.freq=1	//Sets frequency to 1 Hz
wm.samplerate=8K	//Sets sample rate to 8000 samples/second
wm.pk2pk=2	//Sets peak-peak voltage to 2V
wm.offset=0	//Sets DC offset voltage to 0V
wm.reclen=16000	//Sets record length
wm.gui.title="Mod Setup"	//Sets the gui window title

//Carrier Signal Generator
load wc="SigGen"	//Loads the SigGen module. This module can generate waveforms of different shapes.
wc.type="sine"	//Sets signal type as sine
wc.freq=1K	//Sets frequency to 1 KHz
wc.pk2pk=2	//Sets peak-peak voltage to 2V
wc.offset=0	//Sets DC offset voltage to 0V
wc.fm.on=1	//Turns FM input port ON
wc.fm.gain=1K	//Sets FM port gain to 1KHz/V
link wc.fm=wm.out	//Links wc synth's FM input port to wm synth's output port
wc.gui.title="Carrier Setup"	//Sets the gui window title

//Sound Card Exporter
load snd="SoundExp"	//Loads the SoundImp module. This module can convert input data to sound.
link snd.src=wc.out	//Links sound data source to wc synth's output
snd.gui.wnd="snd1"	//Sets the sound gui window name to "snd1"
snd.gui.title="Sound Setup"	//Sets the sound gui window title to "Sound Setup"
snd.gui.move(500,0)	//Moves the sound gui to (x=500, y=0)

//Plot
load p1="Plot"	//Loads the Plot module. This module can display input data in various formats.
p1.plot.title="Plot Window"	//Sets the title of the plot window to "Plot Window"
p1.setup.title="Plot Setup"	//Sets the title of the plot setup window to "Plot Setup"
link p1.src.ch1=wm.out	//Links the mod signal output to Plot input
link p1.src.ch2=wc.out	//Links the carrier signal output to Plot input
p1.ch1.label="Mod Input"	//Sets the Plot ch1 label
p1.ch2.label="FM Output"	//Sets the Plot ch2 label
p1.ch1.vposition=0	//Sets ch1 vertical position to 0
p1.ch2.vposition=0	//Sets ch2 vertical position to 0
p1.setup.move(280,0)	//Moves the plot setup gui to (x=280, y=0)
p1.plot.move(0,220)	//Moves the plot window to (x=0, y=220)
p1.plot.size(1000,420)	//Resizes the plot window to (width=1000, height=420)

<- File ends

Open the above project in DspSee. There will be a sound setup window, a plot window, a plot setup window and a window with Log, modulating signal and the carrier signal GUIs on a tabstrip. Select the desired sound device from the sound setup window. Click on the Run button on the toolbar to start the cycle.

More...

You can use other modules to do following tasks and much more:

SoundImp: Acquire and process data and then play it through sound card. You can make a parrot by sending the acquired audio signal to the speaker (Hint: You need to set the record length to a large number to hold the data for a few seconds).
FileImp: Import data from binary files.
TextImp: Import data from text files.

In summary, the possibilities are endless. Also, many more modules will be availabe in future.