28125 Parallax Inc, 28125 Datasheet - Page 62

• Manufacturer Part Number: 28125
• Description: TEXT ROBOTICS
• Manufacturer: Parallax Inc

Specifications of 28125

• Title: Robotics with the Boe-Bot
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Not applicable / Not applicable

LED Test Circuits
If you completed the What’s a Microcontroller? text, you are no doubt very familiar
with the circuit shown in Figure 2-4. The left side of this figure shows the circuit
schematic, and the right side shows a wiring diagram example of the circuit built on your
board’s prototyping area.
P13
P12
√
√
√
Build the circuit shown in Figure 2-4.
Make sure that the shorter pins on each LED (the cathodes) are plugged into
black sockets labeled Vss.
Make sure the longer pins (the anodes, marked with a ⊕ in the wiring diagram)
are connected to the white breadboard sockets exactly as shown.
What's an I/O pin? I/O stands for input/output. The BASIC Stamp has 24 pins, 16 of which
are I/O pins. In this text, you will program the BASIC Stamp to use I/O pins as outputs to
make LED lights turn on/off, control the speed and direction the Parallax Continuous
Rotation servos turn, make tones with speakers, and prepare sensors to detect light and
objects. You will also program the BASIC Stamp to use I/O pins as inputs to monitor
sensors that indicate mechanical contact, light level, objects in the Boe-Bot's path, and even
their distance.
New to building circuits? See Appendix D: Breadboarding Rules.
470
Ω
Vss
470
LED
Ω
Vss
LED
P15
P14
P13
P12
P11
P10
P9
P8
P7
P6
P5
P4
P3
P2
P1
P0
X2
X3
Vdd
Vin
+
+
Vss
Figure 2-4
Two LEDs
Connected
to BASIC
Stamp I/O
Pins P13
and P12
Schematic
(left) and
wiring
diagram
(right).