Arduino uno User Manual

B00000010, B00000100, B00000000,
-
B00000010, B00000100, B00000000,
-
B00000010, B00000100, B00000000,
-
B00000010, B00000100, B00000000,
20
// ...
-
B00000010, B00000100, B00000000, // 5.5
-
B00000111, B11111110, B00000000,
-
B00001111, B11111111, B00000000,
-
B00011111, B11111111, B10000000,
25
B00111111, B11111111, B11000000,
-
B01111111, B11111111, B11100000,
-
B01111111, B11111111, B11100000,
-
B11111111, B11111111, B11110000,
-
B11111111, B11111111, B11110000,
30
B11111111, B11111111, B11110000,
-
B11111111, B11111111, B11110000,
-
B11111111, B11111111, B11110000,
-
B11111111, B11111111, B11110000,
-
B01111111, B11111111, B11100000,
35
B01111111, B11111111, B11100000,
-
B00111111, B11111111, B11000000,
-
B00011111, B11111111, B10000000,
-
B00001111, B11111111, B00000000,
-
B00000111, B11111110, B00000000,
40
B00000001, B11111000, B00000000,
-
B00000001, B11111000, B00000000,
-
};
-
This file looks weird at first, but it’s really simple. First, we include Arduino.h
because we’ll need to declare binary constants later. After that, we include
avr/pgmspace.h because we want to store our image data in the Arduino’s flash
RAM. Eventually, we include thermometer.h because we need the declaration of
our thermometer image data.
In line 4, we eventually define the thermometer variable we declared in thermome-
ter.h . The definition differs slightly from the declaration because it contains
the PROGMEM directive.
5
This directive tells the compiler to copy the data stored
in the thermometer variable to the Arduino’s flash memory. Usually, when you
define a variable in an Arduino program, it occupies memory in the SRAM.
Most Arduinos don’t have a lot of SRAM (the Arduino Uno only has 2 KB), so
it’s a valuable resource and you shouldn’t waste it. As a rule of thumb, you
should store all constant data in the Arduino’s flash RAM. Use SRAM only
for information that might change during program execution.
5. http://arduino.cc/en/Reference/PROGMEM
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Arduino uno Specifications

General

Form factor	Arduino
Certification	RoHS, FC, CE
Processor model	-
Processor frequency	- MHz
Microcontroller model	ATmega328
Microcontroller frequency	16 MHz
DC input voltage	7-12 V
Operating voltage	5 V
DC current per I/O pin	40 mA
Flash memory	0.032 MB
Maximum internal memory	- GB
SRAM (Static Random Access Memory)	2 KB
EEPROM (Electrically Erasable Programmable Read-Only Memory)	1 KB
Wi-Fi	No
Number of analog I/O pins	6
Number of digital I/O pins	14

Weight and Dimensions

Board dimensions	53.4 x 68.6 mm