Application Notes

Application notes provide indepth technical information about ScreenKeys, ScreenKey development, and supporting toolsets. These are provided to assist developers new to ScreenKeys and for experienced developers looking for new ScreenKey development ideas.

Interfacing to ScreenKeys

APP1001: Introduction to interfacing a microcontroller to a ScreenKey

This note describes a basic method of how to implement a very simple interface to a ScreenKey. Just two interface lines are required; one for data and one for clock. This method is provided as a means to learn and understand the ScreenKey command set.

It is not recommended to use this approach in end-user designs. Instead the approach described in APP1002 is recommended.

Application note APP1001
Sample Schematic using Atmel 80C55WD
Firmware source-code

APP1002: Interfacing ScreenKeys to a Microcontroller

This application note describes an effective method for interfacing ScreenKeys to a microcontroller using a hardware generated clock. This design uses an Atmel 89C55WD microcontroller and uses parallel-to-serial converters to generate serial data for the ScreenKey.

Application note APP1002
DemoComII Schematic using Atmel 80C55WD
Firmware source-code

Full DemoComII Source Code

Note: The Application Notes below are not yet populated, please check back in the next few weeks.

Manipulating Text and Graphics

APP1003: Text to Graphics conversion using pseudo proportional spaced font

ScreenKeys display data as bitmapped graphics devices. However, most often text is displayed on the key. Text must be converted into a suitable graphic format to display this text. This application note describes a useful method to perform this conversion. The note also describes a useful method for implementing a proportional spaced font to maximise the amount of text that can be displayed.

Application note APP1003
Example ‘C’ code

APP1004: Generating graphics for embedded systems design.

The display part of a ScreenKey is a bitmapped graphics device. Each pixel on the display corresponds to a bit location in the ScreenKeys memory. The actual bitmapping is not always in the user’s perspective and requires some bit manipulation. This application note describes how a user’s perspective image can be easily converted into the actual format used by ScreenKeys.

Application note APP1004
Firmware source-code

Windows Tools and Programming

APP1005: Using SAC Controller with Windows Notepad

Integrating ScreenKey techno logy in Windows environments is greatly simplified using the SAC Controller. This utility enables users to easily implement a ScreenKey solution with a third-party application without change to that application. This application describes how to implement a simple interface using an OEM-5400 with Windows Notepad.

Application note APP1005
SAC File

APP1006: Integration of ScreenKeys into a proprietary application using SAC Engine

Proprietary Windows applications can benefit much more from ScreenKey technology by using the SAC Engine to provide dynamic interaction between the proprietary application and a ScreenKey menu system. This application note describes how to implement the SAC Engine with an example application written in VB.

Application note APP1006
SAC File

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