POS Development has some special challenges, ie. printer languages such as ZPL, "ESCPOS", OPOS etc. etc. It would really be nice to know where are the best sites with information and code snippets and sample programs.
Many programs and examples for barcodes for instance, generates barcode images - this is not what I am after - it is about direct comms with the POS devices.
Thanks in advance?
Microsoft has a class library for handling POS. Check it out here: http://msdn.microsoft.com/en-us/library/bb429024.aspx
"Microsoft Point of Service for .NET v1.12 is a class library that enables POS developers to apply Microsoft .NET technologies in their products. It provides a simple and consistent interface for.NET Framework applications to interact with POS devices, a set of interfaces and classes created to help Vendors write applications for common devices such as Cash Drawers or Line Displays, and support for Windows Plug and Play functionality. The following documentation can help you use POS for .NET to develop POS applications and Service Objects (SOs) more efficiently, learn more about the benefits of POS for .NET, and achieve better compatibility with POS devices."
You should check out the open source software solutions currently in the POS vertical. You can at the very least explore the code to see how certain things are done, particularly in interfacing with the hardware.
Perhaps you could even adopt one of them instead. At the very least I'd recommend contributing to these projects if you can.