- The most common method of
reading printed QR Code barcodes is with a camera-based
(aka: barcode imager). Most of the hand-held barcode imagers
recommended by IDAutomation perform keyboard emulation and
receive power from the USB port so that no external power
supply is needed. When a QR Code barcode symbol is read
using keyboard emulation, the data appears at the cursor
as if it had been typed in from the keyboard.
- When reading QR Code barcodes from the screen of an
iPhone, Droid, Blackberry, Windows Phone or other mobile
device, it is necessary to use an advanced imager such as
IDAutomation 2D USB Scanner. Advanced 2D Imagers also
read from LCD and LED screens, as
in this video.
barcode imagers have the ability to read QR-Code barcodes
by default, such as the
and Honeywell Barcode Imagers. Many hand-held
imagers also read very small symbols, such as the
IDAutomation 2D Omni-Directional Scanner, which reliably
reads the IDAutomation
QR-Code Barcode Font when printed as small as 3 points,
which is an X-dimension of 10 mils.
- In many cases, it may be desired to have the scanner trigger a form or action in an application. IDAutomation has documented simple methods of accomplishing this task in the USB Barcode Scanner Application Integration Guide.
- QR Code allows
codes to be easily encoded for various functions such
as tabs and returns. These functions are not usually visible
when scanned unless the
Scanner ASCII String Decoder is used with a scanner
that has lower ASCII capability such as the
Honeywell Xenon 1900 Barcode Imager or
IDAutomation 2D Barcode Scanner with Control + ASCII mode
In all IDAutomation products, the tilde (~) may be used to encode ASCII functions according to the documentation. For example; ~d009 is used to encode a tab and ~d013 encodes a return. In many development environments, Chr or Char may also be used to encode the ASCII value directly. For example, the programming examples below encode "ECC" <tab> 200:
Java: DataToEncode= "ECC" + (char)9 + "200";
Visual Basic: DataToEncode= "ECC" & Chr(9) & "200"
It is possible to scan and encode international and extended characters provided the instructions below are followed:
- Encode the data using byte encoding.
- Scan the data via the serial interface option (data bits have to be 8N) on the scanner. Normally, keyboard wedges and USB scanners do not support extended characters above ASCII 128, and only scan characters that are actually on the keyboard. Contact the scanner vendor for more information as some of the scanner's internal settings may need to be changed.
- It is recommended to limit the amount of data encoded
in each symbol to 800 characters or less if possible. The
ISO/IEC 18004 specifications state that up to 2900 bytes
and 4200 ASCII characters may be encoded in single symbol;
however, few imagers can dependably decode symbols that
large. The amount of data that can be encoded will vary
depending upon the type of data, the encoding mode and what
the scanner can read. In ASCII or text mode, the amount
of data that can be encoded is significantly decreased due
to mode switching between different types of characters,
such as between numbers, upper case, lower case and punctuation.
Most camera based imagers and hand-held scanners have difficulty reading symbols that contain over 800 characters. In the best case scenario, up to 1200 ASCII characters have been successfully encoded and read by using the text encoding mode of the IDAutomation QR Code Barcode Font with the IDAutomation 2D Barcode Scanner.
QR Code Barcode Fonts,
use the tilde character "~" to recognize special characters
when "Apply Tilde" or "Process Tilde" is enabled. The following
tilde options are available:
- ~dNNN: Represents the
ASCII character encoded by the 3 digits NNN.
- For example:
~d009 represents a tab,
~d013 represents a return and
~d065 represents the character 'A'.
- For example:
- ~dNNN: Represents the ASCII character encoded by the 3 digits NNN.
- Denso Wave, Inc. invented the QR-Code symbology. A notification on their website states that no license or royalty fees are required for use provided that a proper copyright notice is included that refers to Denso Wave, Inc. as the copyright owner.