An important element of the automatic control system for a store, warehouse or other enterprise is a barcode scanner for a computer. This device converts the information recorded on the product label with the help of strokes into a record with the name of the product.
Types of barcode readers
Before you purchase and install this device, it will be useful for you to know what barcode scanners are. Special literature distinguishes such models of devices with LED and laser illumination.
Barcode Reader
A Wand barcode scanner for a computer, or as it is also called a pen, is an inexpensive and reliable device. When working, you need to press it well to the surface on which the code is applied, and draw it along the entire package. To read information, he uses a light source of low power, the beam of which must cross the code from beginning to end.
CCD devices
A hand-held CCD barcode scanner for a computer uses technology for reading information, based on the same principle as in faxes. There are two types of CCD scanners: contact and non-contact. When using the contact model, the operator needs to attach the scanner to the label with the code and press the button. The main disadvantage of such scanners is that they do not work well on uneven surfaces. The design of non-contact CCD scanners uses powerful LEDs and sensitive photo sensors, which allows them to read the image at a distance of 6 to 30 centimeters.
An image scanner, or as they are also called a photo scanner, uses the same CCD matrix as cameras or camcorders. This code scanner reads all the information completely and does not need to be specifically oriented with respect to packaging.
Laser readers
The handheld laser barcode scanner for a computer is convenient and easy to operate. Its working area can reach 20-110 centimeters, and for some up to 10 meters.
Multipath laser scanners
A stationary multi-beam projection laser scanner forms a working area, which consists of several beams. In order for him to read the information, it is enough that at least one of the many rays crosses all the strokes. Such devices are of two types: built-in, which are installed in the cash register counter, and projection.
The combined multi-beam scanner is designed in the same way as the stationary one, its main distinguishing feature is that it can be picked up. The working area in which the recognition of barcodes (barcodes) of such devices is reduced compared to stationary ones.
The bioptic scanner creates two working areas in which there are many laser beams. There are models of such scanners equipped with scales.
How to install a scanner to read a barcode?
Before using the scanner, you need to connect it to the computer and install the necessary software. There are three types of devices by the way it is connected to a computer:
1. "Into the keyboard break."
2. Using a serial COM port (as it is also called RS232).
3. Using a USB port that emulates an RS232 interface.
Let us consider in more detail all three connection methods.
Connecting a device for reading a barcode “into a keyboard gap”
The keyboard port is called PS / 2 and is used to connect both a keyboard and a mouse to a computer. Now many motherboards have only one such connector, and in modern netbooks and laptops it is absent.
To connect a keyboard reader, you must first turn off the computer, remove the keyboard from the connector, and insert a scanner instead. After that, you need to connect the keyboard to the scanner. After you have connected everything, you can turn on the scanner and computer in the electrical network.
After scanning the barcode with a device equipped with this interface, the code is inserted where the cursor was, as if you had typed it on the keyboard. Thus, if the scanner cannot read the code or is out of order, you can enter the code directly using the keyboard.
Those involved in scanning barcodes with a device with a similar interface should pay attention to the keyboard layout when recognizing serial numbers that contain letters. For example, when the Russian keyboard layout is on, instead of the code a / n123215654QWE, f / t123215654YTSU is considered.
This connection method saves one COM or USB port, which can be useful when connecting to a computer many different devices, for example, a receipt printer , fiscal printing device, scales and other devices necessary for the cashier to work. Also, a barcode scanner with a “keyboard break" connection is used when using a barcode program that can only work with similar devices.
Installing a barcode reader using the COM interface
COM or RS-232 port - these are two different designations of one interface, through which various devices can be connected to a personal computer. This connector is made in the form of a rectangle, which consists of two rows of pins (in one row 5, in the other 4). Information from a variety of external devices, using this method of transmission, arrives sequentially, via two wires. Through the wire Rx, information enters the computer, and through Tx the control signals are transmitted to the device. Sometimes, for the correct operation of programs, additional RTS and CTS lines are used. Now you can still find motherboards with one RS-232 connector, but it is not available on all modern netbooks and laptops.
To install the scanner, you must first connect it to the computer’s COM port, after which any operating system will find it and ask you to install the necessary drivers. They can be found either on the disk that comes with the device, or download on the Internet. Some scanner manufacturers provide special programs with which you can control the volume of the signal or set service symbols.
The barcode scanner can be connected to the computer using a special adapter from USB to COM-interface, which must be inserted into USB and the driver must be installed (special program for barcode scanner). If the device is installed correctly in the system, a virtual interface of the RS-232 standard will be detected, the use of which should not be much different from working with a normal serial connection.
A barcode scanner with a COM port can be connected to a POS terminal, cash register or other equipment that is equipped with an RS-232 interface. For such a connection, adapters from the connector used in the barcode reader to the RJ-45 connector (or 11) are used. After that, you need to configure the connection settings in the scanning device.
Also, this type of connection is used if the code scanner program specifically listens to the port and, when a code is detected, inserts it into the right place. It doesn’t matter where the cursor is currently located.
How to connect a barcode scanner of a computer with a USB interface?
Any modern computer, netbook, laptop is equipped with a USB port. In this standard, data is transmitted sequentially through two wires, two more wires serve to supply voltage to devices that connect to a PC.
The main advantage of these devices for reading the barcode of a computer is their high speed of data exchange and the ability to connect to a working computer. Small handheld barcode scanners consume a small amount of power, so they are powered from a USB port. Multiplane readers are more powerful and therefore have a separate power supply.
Installing a scanner should not be difficult, because all modern operating systems recognize the device for reading codes as a regular keyboard, so they do not require any drivers for their work. After the barcode is scanned, the program inserts it where the cursor is.
Many barcode scanners that plug into a USB port can be made to work in a mode in which it will emulate an RS-232 port. Most often, this requires reading a special barcode, which is given in the instructions and installing the virtual port driver. After putting the device into COM-interface emulation mode, its use will be the same as for a conventional scanner working with the RS-232 standard.
In many readers, it is possible to set the characters that will be transmitted before and after the barcode. So, before reading the code, it would be convenient for many users if the scanner transmitted one of such characters as Insert, F1, or F9. Thanks to this feature, the number of keystrokes by the operator is reduced and its operation is facilitated.
Checking the correct connection and scanner functionality
After the installation of the barcode scanner is completed, you need to check the operation of the device.
In order to make sure that the scanner connected “to the keyboard break” or via the USB connector works correctly, you need to start any text editor, such as Notepad, and try to scan the code. If symbols appear on the screen, the device is configured correctly.
If your device for reading barcodes is connected to RS-232 or works via USB in the COM interface mode, then you first need to run any terminal program and configure it to the desired port. After that, you can read the code from the package. When correctly configured, readable characters should appear on the screen.