Retail POS FAQs

How Do Scanners Work?

A basic bar code scanner consists of a scanner, a decoder, and a cable that interfaces between the decoder to the computer or terminal. The scanner's function is to scan the bar code symbol and provide an electrical output to the computer that corresponds to the bars and spaces of the bar code. However, it's the decoder that recognizes the barcode symbology, analyzes the content of the bar code scanned, and transmits that data to the computer in a traditional data format. A scanner can either have the decoder built into its handle or be "un-decoded" which requires a separate box, called an interface or wedge. Un-decoded scanners are also used when connecting to portable batch terminals as the decoding is performed by the terminal itself.

Keyboard Wedge Readers

A keyboard wedge reader is attached to a computer through a port called the keyboard interface. When a bar code is scanned, the information is transmitted as though it were keyed in from the keyboard. Sometimes they're referred to as wedge readers because they physically wedge between the keyboard and the computer and attach as a second keyboard. One great advantage of a keyboard wedge is that bar code reading can be added with no software changes necessary; the software thinks that the data received was entered by a speedy typist. With a wedge reader, any program that accepts keyed data will accept bar code data with no change.

Serial Bar Code Scanners

Another way to transmit data from a bar code reader to a computer is to connect it to the computer's RS-232 serial port. The bar code information read will be transmitted in ASCII format and look just like keyed data to the computer. Using a serial port connection is ideal for a multi-user computer. With serial ASCII terminals for each user, the bar code reader can attach between the terminal and host computer and transmit ASCII data just like the terminal.

Portable Batch Scanners

Portable batch scanners are hand-held battery operated readers which store data in memory for uploading to the host at a different time. A portable batch reader contains a bar code scanner, an LCD-display to prompt the user to perform a task, and a keyboard to enter variable data such as quantities. A cradle must also be purchased to upload information to the computer. Portable batch scanners are ideal when mobility is a must and when collected data isn't immediately needed. These scanners come in a variety of styles including hand-held, wearable and truck mounted. Your application will determine which style is best.

Wireless Portable Scanners

When you need to collect information at a remote location, and need the information immediately, a wireless solution is the perfect one. A wireless scanner is also built into a terminal, and uploads data to the host as it's scanned, instantly and accurately. Wireless products let the user scan the information at the point of activity which makes it ideal for many industries.

Cables

The cable required depends upon how you need to connect the scanner. Cables are either RS- 232 direct cables or Synapse adapters and all require a power supply. RS-232 connections have either 9 or 25 pins and connect the scanner to the PC. A Synapse adapter enables you to use one scanner with a variety of different PCs by simply changing the Synapse adapter cable.

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