POS for .NET and OPOS

OPOS is an existing implementation of UPOS for Microsoft Windows, based on Component Object Model (COM) technology. POS for .NET constitutes an improved, next-generation implementation of UPOS for Microsoft Windows, based on .NET. In comparison to OPOS, POS for .NET increases productivity of developers of both POS applications and service objects, by providing all the benefits of .NET managed code while at the same time exposing a set of easy to use interfaces and base classes.

POS for .NET is backward-compatible with OPOS version 1.8 service objects. In other words, applications using POS for .NET can simultaneously interact with .NET service objects written for POS for .NET and OPOS service objects.

POS for .NET Device Basic Classes

Each hardware device in POS for .NET is represented by both an abstract interface, such as CashDrawer class, and a “basic” class, such as CashDrawerBasic. Basic classes derive from the underlying interface and contain basic functional support for the device. POS for .NET provides generic support for opening, claiming, and enabling the device; device statistics; and management of delivery of events to the application. In addition, each basic class contains a set of inherited and protected methods that can be implemented by the service object. This topic provides summary information about basic classes that can be used by service objects that wish to derive from the device’s basic class, rather than taking advantage of the more fully implemented device base class

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