28123 Parallax Inc, 28123 Datasheet - Page 47

• Manufacturer Part Number: 28123
• Description: TEXT WHAT'S A MICROCONTROLLER
• Manufacturer: Parallax Inc
• Type: Programmingr

Specifications of 28123

• Style: Book
• Title: What's a Microcontroller?
• Contents: Whats a Microcontroller? Text
• Product: Microcontroller Accessories
• Core Processor: PIC16C57c
• Flash: 128 Bytes
• Operating Supply Voltage: 9 V
• Board Size: 31 mm x 16 mm
• Lead Free Status / RoHS Status: Not applicable / Not applicable

An LED circuit can be connected to the BASIC Stamp, and the BASIC Stamp can be
programmed to connect and disconnect the LED circuit’s power. This is much easier
than manually changing the circuit’s wiring or connecting and disconnecting the battery.
The BASIC Stamp can also be programmed to do the following:
ACTIVITY #1: BUILDING AND TESTING THE LED CIRCUIT
It’s important to test components individually before building them into a larger system.
This activity focuses on building and testing two different LED circuits. The first circuit
is the one that makes the LED emit light. The second circuit is the one that makes it not
emit light. In the activity that comes after this one, you will build the LED circuit into a
larger system by connecting it to the BASIC Stamp. You will then write programs that
make the BASIC Stamp cause the LED to emit light, then not emit light. By first testing
each LED circuit to make sure it works, you can be more confident that it will work when
you connect it to a BASIC Stamp.
Introducing the Resistor
A resistor is a component that ‘resists’ the flow of electricity. This flow of electricity is
called current. Each resistor has a value that tells how strongly it resists current flow.
This resistance value is called the ohm, and the sign for the ohm is the Greek letter
omega: Ω. The resistor you will be working with in this activity is the 470 Ω resistor
shown in Figure 2-2. The resistor has two wires (called leads and pronounced “leeds”),
one coming out of each end. There is a ceramic case between the two leads, and it’s the
part that resists current flow. Most circuit diagrams that show resistors use the jagged
line symbol on the left to tell the person building the circuit that he or she must use a 470
Ω resistor. This is called a schematic symbol. The drawing on the right is a part drawing
used in some beginner level Stamps in Class texts to help you identify the resistor in your
kit.
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Turn an LED circuit on and off at different rates
Turn an LED circuit on and off a certain number of times
Control more than one LED circuit
Control the color of a bi-color (two color) LED circuit