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System - grupa urządzeń
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A bar code scanner, whether a CCD or laser, hand-held or fixed, is simply a device that provides a quick and easy way to transfer the information contained in a bar code to another device. A bar code scanner is much like a modem in that it is not very useful without a computer to receive the information, software to process the information, and a monitor or printer to view what has been received and processed.
There are many different types and complexities of bar code systems. The type of system required is determined by the application for which the scanners are being used. A basic scanning system could consist of a bar code scanner, a decoder, a computer and a printer. The components that connect to the computer are known as peripherals.
The bar code scanner sees the bar code information as a reflection of emitted light. An image of the illuminated bar code is received at the scanner because the spaces of the bar code reflect more light than the bars. This image is then converted into a digital (ones and zeros) electrical signal proportional to the bars and spaces of the bar code. This process occurs in all scanners and for a non-decode scanner, like the MS941, the digital electrical signal is sent through the cable to an external decoding device. Other scanners, such as the MS951 and the MS700i, offer on-board, internal decode. The decoder's job in the system is to convert the digital data back into the encoded characters, "0123" in this example. The decoder then sends the "0123" to the host computer or device in ASCII format, a common data format used by many computer systems.
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Once this information is sent from the decoder, the software running on the computer ( the "Application Program") determines what then happens with the data.
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Generally, an application will cross-reference the bar code to some price or item file in memory, or store the decoded bar code data in a file for later access. Hard copy data can be generated by the system's printer and information can be uploaded to a mainframe or network to which the computer may be connected. This system is essentially the same for a point of sale (POS) system; however, the printer is usually replaced by a register tape, the monitor with a display panel, and a cash drawer is usually added. This is simply a special type of computer called an electronic cash register.
These are just two examples of bar code systems. Many other types of systems exist: portable, industrial, verification and real-time radio frequency. Understanding the end-users' application will help you guide them to the most appropriate system selection.
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