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Developer Guide for Symbol Technologies Devices1-4
DOS to CE
Despite advances in operating system technologies and the increasing adoption of wireless technologies throughout the global
business environment, many enterprises using mobile technology have continued to make investments in DOS-based applications.
Although this approach has worked successfully for many, continuing to develop to legacy technologies prevents DOS-based
enterprises from evolving into agile businesses capable of capturing, moving and managing data efficiently.
Unlike contemporary operating systems, DOS was designed to perform a single task at a time. A program was loaded from storage
to memory, executed to perform a task, and then exited. The total memory supported was limited to 640KB. The user interface was
character-based; mass storage was limited; and mobile technology was not yet available. Since multimedia was in its infancy, no one
imagined that Web browsing, video display or audio output would be possible, let alone widespread, on devices.
With the advent of the Microsoft Windows CE operating system, the world of mobile computing changed for the better. Graphical
user interfaces (GUIs) made applications easier to use. Increased memory and storage space in Windows devices led to more
functionality being available on devices, which in turn resulted in increases in end-user productivity. Windows CE provided the ability
to add new technologies to devices without having to rewrite applications. In a nutshell, Windows CE provides a more advanced
toolset and a larger development community. This is why Symbol chose Microsoft Windows CE as a development platform, and
Symbol Mobility Developer Kit as the tool to write applications for that platform.
SDK to SMDK
Prior to the introduction of the SMDK, each Symbol device required a dedicated C Language SDK to write applications for that device.
Using the device specific SDK approach, by the end of 2004, more than 100 SDKs would have been supported out in the field.
In addition to managing a large number of device specific SDKs, problems arose due to potential SDK conflicts across devices, no
central ownership, a different look and feel for each SDK, and requirements for supporting additional languages such as Java, C# and
VB.NET.
To enhance the customer experience, the Symbol software team developed a "common" SDK model for Pocket PC 2003, Windows CE
4.2, Mobile 5.0 and Windows CE 5.0 devices. The new SDK model takes the traditional device-specific C Language SDK and splits it
into two separate products:
• a "common” SDK, called the SMDK for C, used for developing applications
• a number of DCPs, one for each type of device, used for deploying software.
Microsoft Windows Mobile 5.0 devices do not have DCPs.
The SMDK for eVC4 contains all of the files necessary for creating applications for Symbol devices. It includes an API reference guide,
a set of sample applications and the Symbol library files.
The DCP contains all of the files necessary for customizing the Platform and Application partitions of a device. It includes a utility
program that allows users to customize and load HEX images and documentation describing how to use and configure the device and
its accessories. Some DCP releases include a utility program that allows users to create REG files for setting device options.
Due to the high demand for additional programming models, Symbol now produces SMDK products for C/C++, Java, .NET and the
Web.
This new SDK model provides a set of tools that are more flexible, allowing customers who simply want to load devices to do so
without having to install third party developer tools and a full SDK. It also allows customers to create applications for a wide variety
of Symbol devices using a single developer kit.