Barcode Decoders Information
Barcode decoders are hardware devices that convert the information in barcodes to a digital format. They analyze a barcode’s bars and spaces, determine that the data is from a valid barcode, and then identify the correct barcode symbology. Check digits at the beginning and end of the barcode are added to an ASCII text file that is sent to a host computer, typically a PC. Some barcode decoders have text-formatting features that remove the leading digits from a string, add a character to the beginning of the string, or convert numbers to letters. Programming is performed on the barcode decoder itself, or via software on the host computer. Keyboard wedge decoders can be used with laser, wireless, and charged coupled device (CCD) barcode scanners; slot, badge, and magnetic stripe readers (MSRs); and barcode wands and barcode wand scanners. As wedge-style barcode decoders, these devices are designed to plug directly into a computer’s keyboard port, and are equipped with a connector for use with the computer’s keyboard. As their name suggests, USB decoders are designed to connect to a PC via its USB interface. Barcode decoders that use other serial interfaces and serial protocols are also available. Decoding devices for magnetic stripe readers may provide support for single or dual tracks, and permit the bi-directional swiping of cards. Product specifications for barcode decoders include power, programmability, interface, special keys, termination characters, and decode rate. Although most decoding devices receive their power through the computer, battery-powered barcode decoders do not. With regard to programmability, some products feature a setup menu and DIP switches. For keyboard or wedge barcode decoders, the type of connector may vary. The interface is typically keyboard or USB, but wireless barcode decoders are also available. Support for special keys and termination characters are required for some decoding applications. The decode rate is a measure of a barcode decoder’s speed. Different barcode decoders support different barcode symbologies. These symbologies are essentially alphabets in which different widths of bars and spaces are combined to form characters and, ultimately, messages. Choices include Codablock and Codabar; Codes 11, 128, 16K, 39, 49, 93; Data Matrix (Data Code); Industrial 2 of 5, Interleaved 2 of 5, and Matrix 2 of 5; MaxiCode, Plessey, and NW-7 Code; PLANET and POSTNET; TelePen, UPC, and Vericode. Barcode decoders that support other barcode symbologies are also available.