28139 Parallax Inc, 28139 Datasheet - Page 200

• Manufacturer Part Number: 28139
• Description: KIT REMOTE IR FOR BOE-BOT W/TEXT
• Manufacturer: Parallax Inc

Specifications of 28139

• Accessory Type: IR Remote
• Product: Microcontroller Accessories
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• For Use With/related Products: Boe-Bot®
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Contains lead / RoHS non-compliant

the Boe-Bot kits. However, the missing parts are inexpensive, easy to obtain, and they
can also be ordered from Parallax. The Parallax part numbers for the extra parts are
included in the parts list below.
(1) Capacitor - 0.01 µF
(1) Resistor - 470 Ω (Yellow, Violet, Brown)
(2) Resistors - 220 Ω (Red, Red, Brown)
(1) IR LED
(6) Jumper wires
(1) Potentiometer - 10 kΩ
(1) NE555N timer IC
Pulse Controlled 38 kHz Transmitter Circuit
Figure C-1 shows the IR transmit circuit. The 10 kΩ potentiometer in this circuit has to
be adjusted so that it transmits 38 kHz. The BASIC Stamp can be programmed to
monitor and report the frequency transmitted by the 555 timer's Out pin with P7. When
the correct transmit frequency is established, the BASIC Stamp can then be programmed
to control the durations the 555 timer transmits 38 kHz by sending
555 timer's Res pin with P6.
Parallax Part#: 152-01031
Parallax Part#: 604-00009
√
√
If you are using the 10 kΩ potentiometer with the Parallax Part#: 152-01031,
pinch each of its legs with a needle-nose pliers to remove the kinks and
straighten them before inserting the part into the breadboard.
Build the circuit shown in Figure C-1 on a second board, which you will use to
beam IR remote messages to your board with a receiver circuit (or a Boe-Bot
with IR object detection circuits).
To learn more about designing 555 circuits for transmitting various frequencies and duty
cycles, download the Basic Analog and Digital PDF from www.parallax.com, and read the
first five pages of Chapter #6.
PULSOUT
signals to the