28128 Parallax Inc, 28128 Datasheet - Page 121

• Manufacturer Part Number: 28128
• Description: KIT BASIC ANALOG/DIGI PARTS ONLY
• Manufacturer: Parallax Inc

Specifications of 28128

• Accessory Type: ADC, DAC
• Product: Microcontroller Accessories
• For Use With/related Products: BASIC Stamp® 2 and Board of Education
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Chapter 6: Recording Frequency Data · Page 111
The Output
Figure 6-5 shows the Stamp-O-Scope 2 display. You can adjust the potentiometers and
change the frequency characteristics of the waveform. For example, pot B directly affects
the amount of time the signal is low. It also indirectly affects the amount of time the
signal is high. Try adjusting pot B until the low signal is 4 asterisks wide. Then, you can
adjust pot A so that the pulse-width varies. Try adjusting A so that the pulse-width is also
5-asterisks wide. Toggle the Pause/Resume button on the Debug Terminal by clicking on
it with your mouse to freeze and unfreeze the display.
Figure 6-5: Output Sample of 555 Timer Pulse Train
This is a time-varying display of the pulse train generated by the 555 timer as measured
by pin P0. Again, the display has been turned sideways to match conventional displays
and graphs.