Thursday, June 25, 2009

Exploit The SoundCard as Oscilloscope

Thanks to Konstantin Zeldovich

Oscilloscope for Windows version 2.51 (Oscilloscope 2.51) is an application showing how home PC peripherials, such as a sound card, can be used in an unconventional way, emulating industrial ADC hardware. The Oscilloscope provides a complete functionality of a "standalone" scope in a familiar Windows ennvironment.

The Oscilloscope allows you, for example:
- to study in real time any signal envelope,
- to measure frequencies
- to study realtime signal spectra,
- to plot Lissajous patterns.
- to measure a cross-correlation coefficient of two signals
(In general, to do most things you can do with an oscilloscope and a spectrum analyzer).


Not surprisingly, the Oscilloscope has several drawbacks too:
- non-calibrated amplitude level (hard to use as digital multimeter),
- relatively low bandwidth (20 Hz - 20 kHz),
- possibility of damage of a PC when connecting to an unknown signal source. (See Precautions ).



Specifications:
Dual trace digital storage oscilloscope with realtime spectrum analyzer and correlometer.
Buffer length: 52 ms
Bandwidth: 20 Hz - 20 kHz max
Input level: about 2 VAC, limited by sound card capabilities
Display refresh: ca. 6 fps
Data export: disk file or Windows clipboard, text format

Click here to download the oscilloscope software

Tuesday, June 23, 2009

USB Sniffer With SnoopyPro

SnoopyPro is a tool for advanced USB programmers. It allows you to record each URB sent to and received from a USB device. This traces can be saved, loaded, edited, printed and combined into new traces.

WARNING: You might damage your system with this tool. Don't use it if you don't know what you're doing!!!! We're not responsible for anything that happens to you, your system, your devices, your marriage, etc. etc.

SUPPORTED OPERATING SYSTEMS:

Tested by the authors on Windows 98, Windows 2000, Windows XP

INSTALLATION/USE:

1. Run SnoopyPro.exe from whereever you have saved it.
2. Open up the USB devices window with F2.
3. Choose 'Unpack Drivers' from the 'File' menu.
4. Choose 'Install Service' from the 'File' menu.
5. Locate the device you want to sniff.
6. Right-click on it and choose 'Install and Restart'.
7. Wait for the magic to happen...




Click Here To Download SnoopyPro

Saturday, June 20, 2009

The Toolbar in LabVIEW

The Toolbar, located at the top of LabVIEW windows, contains buttons you will use to control the execution of your VI, as well as text configuration options and commands to control the alignment and distribution of objects (see Figure 59). You'll notice that the Toolbar has a few more options in the block diagram than in the front panel, and that a few editing-related options disappear when you run your VI. If you're not sure what a button does, hold the cursor over it until a tip strip appears, describing its function.

Figure 59. Toolbar




Run Button

Run Button (Active)

Run Button (Broken)

The Run button, which looks like an arrow, starts VI execution when you click on it. It changes appearance to active when a VI is actually running. When a VI won't compile, the run button appears broken.

Continuous Run Button

The Continuous Run button causes the VI to execute over and over until you hit the stop button. It's kind of like a GOTO statement (sort of a "programming no-no"), so use it sparingly.

Abort Button

The Abort button, easily recognizable because it looks like a tiny stop sign, becomes active when a VI begins to execute; otherwise, the Abort button is grayed out. You can click on this button to halt the VI.
Using the Abort button is like pulling the power cord on your computer. Your program will stop immediately rather than coming to a graceful end, and data integrity can be lost this way. You should always code a more appropriate stopping mechanism into your program, as we will demonstrate later.

Pause Button

The Pause button pauses the VI so that you can use single-step debugging options such as step into, step over, and step out. Hit the Pause button again to continue execution.

Step Into Button

Step Over Button

Step Out Button

The single-step buttonsStep Into, Step Over, and Step Outforce your VI to execute one step at a time so you can troubleshoot.

Execution Highlight Button

The Execution Highlight button causes the VI to highlight the flow of data as it passes through the diagram. When execution highlight is on, you can see intermediate data values in your block diagram that would not otherwise appear.

Retain Wire Values

The Retain Wire Values button causes the VI's wires to store the value that flowed through them the last time the VI executed. This is very useful for debugging. You can view the value stored in a wire by placing a probe on the wire. The probe value will be set to the value stored in the wire.

Warning Button

The Warning button appears if you have configured your VI to show warnings and you have any warnings outstanding. You can list the warnings by clicking on the button. A warning is not an error; it just alerts you that you are doing something you may not have intended (for example, if there are objects on the block diagram that are hidden behind other objects and cannot be seen).