Hardware Reference
In-Depth Information
Figure 11.18
600 Hz (approx.) sine wave displayed using Windows
Oscilloscope 2.51 and the sound card interface
Software Oscilloscope uses selectable sampling rates of 11, 22 and 44.1 kHz
(note that the highest rate is only available to registered users). The sound
card needs to operate in full-duplex mode, allowing concurrent recording and
playback. Software Oscilloscope runs with most versions of Windows (but not
Windows NT or Windows 3.x) but it does require DirectX support (see below).
Software
Oscilloscope
requires
the
DirectX
Runtime
module.
Various
versions of DirectX are available including:
Windows version
DirectX compatibility
Windows 98
DirectX 9.0
Windows Me
DirectX 9.0
Windows 2000
DirectX 9.0
Windows 95
DirectX 8.0
Windows XP
Not required
Windows NT
Not supported
Waveform display
Waveform display with a sound card oscilloscope is extremely straightforward.
Sinusoidal signals in the frequency range 20 Hz to 20 kHz can be displayed with
a high degree of accuracy. Figure 11.18 shows a typical sine wave displayed
using Windows Oscilloscope 2.51. Note that the Y1 and Y2 gains are set to 4.38
and that the time for a complete sweep is set to 5 ms (the signal frequency is
