Arduino uno User Guide

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 Mark major sections or functions with a comment header line or two
 Have just the right number of comments, not too few and not too many. Assume the reader
knows the programming language so have the comment be instructive. Here is an example of
an instructive comment
digitalWrite(4,HIGH) // turn on motor
and here is a useless comment
digitalWrite(4,HIGH) // set pin 4 HIGH
You need not comment every line. In fact, commenting every line is generally bad practice.
 Add the comments when you create the code. If you tell yourself, "Oh, I'll add the comments
when the code is finished", you will never do it.
10 Common Coding Errors
 Forgetting the semi-colon at the end of a statement
 Misspelling a command
 Omitting opening or closing braces
Please send comments, suggestions and typo alerts about this guide to wkdurfee@umn.edu
11 Appendix
On the following page is a summary of basic Arduino commands, with examples.

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