122-28176 Parallax Inc, 122-28176 Datasheet - Page 63

• Manufacturer Part Number: 122-28176
• Description: GUIDE STUDENT PROCESS CONTROL
• Manufacturer: Parallax Inc

Specifications of 122-28176

• Accessory Type: Manual
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Propeller Education (PE) Kit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

Challenge 3-2: Photographic Darkroom Alarm
ACTIVITY #3: UNCOMMITED INPUTS AND CONDITIONING SWITCHES
An uncommitted input is one not dedicated to a voltage potential, is said to be “floating”
and may not be sensed by the BASIC Stamp as a definite logic HIGH or LOW. Simply
connecting a mechanical switch between the input and Vdd leaves the input floating
when the switch is open. Current flow to Vdd or Vss is necessary to “commit” the input
(when in the open condition). This exercise will help make this concept clear.
Parts Required
(1) ADC0831
(2) Resistors – 220 Ω
(1) Resistor – 1 kΩ
(1) Resistor – 10 kΩ
(1) Pushbutton – Normally Open
(1) LED – Red
√
Modify the circuit to exceed the threshold when excess light falls on the sensor.
Draw your circuit modifications. Discuss settings and results.
Figure 3-5
Night-Light
Plot