A barcode solution consists of the following:
- a barcode printer
- a barcode reader
- a mobile data collection application/program

A barcode label is a special symbology to represent human readable information such as a material number or batch number
in machine readable format.

There are different symbologies for different applications and different industries. Luckily, you need not worry to much about that as the logistics supply chain has mostly standardized on 3 of 9 and 128 barcode symbologies - which all barcode readers support and which SAP support natively in it's printing protocols.

You can print barcodes from SAP by modifying an existing output form.

Behind every output form is a print program that collects all the data and then pass it to the form. The form contains the layout as well as the font, line and paragraph formats. These forms are designed using SAPScript (a very easy but frustratingly simplistic form format language) or SmartForms that is more of a graphical form design tool. 

Barcodes are nothing more than a font definition and is part of the style sheet associated with a particular SAPScript form. The most important aspect is to place a parameter in the line of the form that points to the data element that you want to represent as barcode on the form, i.e. material number. Next you need to set the font for that parameter value to one of the supported barcode symbologies.

The next part of the equation can be a bit tricky as you will need to get a printer to print that barcode font. Regular laser printers does not normally print barcode fonts, only specialized industrial printers that is specifically designed to support that protocol and that uses specialized label media and heat transfer (resin) ribbon to create the sharp image required for barcodes.

Not to fear though, there are two ways to get around this:
- You can have your IT department do some research - 
most laser printers can accept a font cartridge/dimm chip (similar to computer memory), called a BarDIMM that will allow a laser printer to support the printing of barcodes.
- Secondly, you can buy software that you can upload in your SAP print Server that will convert the barcode symbology as an image that will print on a regular laser printer. I found that this option results in less sharper barcodes. This option is really if you need to convert a large quantity of printers (>10) to support barcodes. 
- Thirdly, you can buy a third party software like Barcode.dll and install on your frontend PC connected to the laser printer.

Now you have a barcode printed - what next?
Well there are two options, depending on your business requirements:
- You can use an existing SAP transaction on a regular workstation and get a barcode wedge reader to hook up between the keyboard and the PC. These wedge readers comes in a wand or scanner format. There are even wireless wedge scanners available that allows you to roam a few yards from the workstation to scan a label. This approach is mostly used where you want to prevent human errors in typing in long material, batch or serial numbers in receiving or issuing of material. The problem is that it's just replacing the keyboard input and you are basically locked down in one location and have to bring all the material to that location to process.
- Another solution is to use SAPConsole transactions
or write your own ABAP Dialog programs that will fit onto a barcode enabled wireless handheld terminal and that will follow the business logic as executed on the shop floor. 

These programs are highly complex exercises in industrial engineering and ergonomics because of the limited screen sizes and limited ability to accept keyboard input. The user is instructed step-by-step and only scan and push F-keys to interact with the SAP system. Scan, scan, beep, beep, enter - highly automated.

SAPscripts Tips by : Ravikumar Kandikonda

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