Download Portable Embedded GUI Programming Manual

Synopsis
for the product without the question of whether or not your GUI has the
ability to come along for the ride.
1.2 What C/PEG Is Not
C/PEG is not a desktop graphical user interface that has been 'stripped
down' in an attempt to fit into the embedded systems market.
C/PEG does not hide the system from the programmer. It does not attempt
to wrap and internalize system functionality that is best left to the
application developer. C/PEG deals strictly with the graphical user interface
of the system. All other functionality for the application is left to the
imagination and skill of the developer. In other words, C/PEG does not
force a 'you can do anything you wish, as long as it's what we wanted for
you to do' type of development environment.
1.2.1 How C/PEG Works
The execution model of C/PEG is very familiar to any programmer who has
ever worked with message driven application models, such as the
venerable Win32 API or the mature X Window System. In this model, user
interface objects participate in a messaging loop whereby the system
notifies the object of certain events. These events may be a by-product of
user interaction with the system hardware, such as incoming key or
pointing device data; operating system notifications, such as timers; or from
interrupts coinciding with external device status. All of these events cause
C/PEG to 'do something'. When these events are dormant, so too is C/
PEG.
This model also facilitates an easy to understand and highly structured line
of communication between C/PEG application objects. It is a very simple
process for C/PEG objects to notify any other C/PEG objects with any type
of system or user defined message.
1.2.2 Benefits of using C/PEG
Building off of the success of the original C++ version of PEG, C/PEG
already has an impressive pedigree and proven track record of enormous
benefits to the embedded systems application developer community.
In this day of hurried product development cycles, C/PEG is a tremendous
asset to any development team. By providing both low and high level
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C/PEG Programming Manual
Swell Software, Inc.