28139 Parallax Inc, 28139 Datasheet - Page 106

• 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

SUMMARY
Decoding is the process of converting an electronic signal into something understandable
and useable. In the case of the IR remote message, decoding involved converting pulse
duration measurements into binary 1s and 0s in a byte variable. Each time the process
completes, the byte variable stores a number (code) that corresponds with a key on the
keypad.
In order to understand the decoding process, the concepts of counting in binary and
binary to decimal conversion were introduced. The
way to set and clear bits in a variable.
pulse measurement to determine the value of a bit in a variable that stores the decoded
value of the remote's pulse width modulated message.
employed the
measurement was above a certain value, or clear the bit if the pulse measurement was
below a certain value.
This chapter developed application programs with constants, variable declarations, and
subroutines that serve as building blocks that you can use in larger programs. These
application programs reduced programs from Chapter 1 that were somewhat challenging
down to a few lines in the application's main routine.
Techniques were introduced for modifying application program examples and using their
features to the Boe-Bot's advantage. Examples included using constants with helpful
names in decision making, calling subroutines to capture IR messages, and adding
variable declarations,
use with the Boe-Bot's servos.
Questions
1. What does it mean to "decode" an IR message from the universal remote?
2. What's a binary digit usually called?
3. How can you figure out the value a particular bit position represents?
4. What does it mean to set or clear a bit?
5. How do you use
6. How are constants used in IrRemoteButtons.bs2?
7. What does it mean when a pushbutton is debounced?
.BIT
modifier to set a bit in a variable if the corresponding pulse
PIN
.BIT
directives and routines that adapt an application program for
to set and clear bits in a variable?
IF…THEN
statements were written that examined
.BIT
modifier was introduced as a
These
IF…THEN
statements