Custom ABCD Proto-Kernel™ Distributions




 

Free Software Distribution Is Not Always Gratis

The Abcd Proto-Kernel™ Website Distribution Is Complete and Useful

CONNOTECH Internally Uses “Source Code Filtering”

Custom Distributions of the ABCD Proto-Kernel™



“Free Software” Distribution Is Not Always Gratis


A common misconception about free software is that it costs nothing. It is true that the ABCD Proto-Kernel™ distribution on the CONNOTECH website is gratis. However, a custom ABCD Proto-Kernel™ distribution may be needed because the source code that CONNOTECH developed is not wholly contained in the website distribution.


A custom ABCD Proto-Kernel™ distribution occurs under the same licensing scheme as the website distribution, with portions covered by GPL-style licensing and perhaps portions of proprietary applications (or even complete proprietary applications).


The ABCD Proto-Kernel™ Website Distribution Is Complete and Useful


The current ABCD Proto-Kernel™ website distribution contains the complete and exact source code required to build the 7 executable programs that it contains. This is in compliance with the following quote from the Free Software Foundation FAQ document: “The sources you provide must correspond exactly to the binaries.”


This freely available package is technically sound because it supports the PPCMB/850 embedded target hardware, thus meeting the “reality check” quality criteria. In addition, it provides a showcase and the foundation for the ABCD Proto-Kernel™ used in other embedded target systems, notably with the application-specific host PCB for the PPCMB/850 that are independently developed.


The ABCD Proto-Kernel™ technical documentation (freely available) is more comprehensive than the source code in the website distribution. Future website distributions should encompass a greater portion of the documented ABCD Proto-Kernel™ technical details.


CONNOTECH Internally Uses “Source Code Filtering”


As part of its software development procedures, CONNOTECH uses CVS for source code control and a unique source code filtering utility that deserves an explanation for the understanding of the actual contents of free software distributions. The source code filtering utility is not released as a free software, mainly because it is very specific to the CONNOTECH software configuration control methodology.


This source code filtering utility generally acts like the C preprocessor in removing unnecessary source code lines between #if / #else / #endif directives, but with a global view of every source files used in building an executable. Filtering is applied to the assembler source files as well. The ABCD Proto-Kernel™ website distribution is prepared such that the filtering applied to a given source file takes into account every instance where it is compiled for any of the 7 executable programs. In this respect, the set of filtered source files are strictly equivalent to the initial source code base, and the makefile procedures apply identically to either the initial or the filtered version.


There are many benefits to the filtering applied to the source code before distribution:

  ●         the filtering process gives the exact source code compiled to create the executable programs,

  ●         the filtered source code is streamlined and easier to understand, enhancing its educational value,

  ●         the streamlined source code is easier to verify and test,

  ●         the streamlined source code compatibility with the target environment configuration is more readily ascertained,

  ●         the streamlined source code is to easier to modify.


The filtering process was first used in an avionics project. The source code filtering step helped in making progress towards certification:

  ●         the exact source code that correspond to the executable had to be submitted to the certification process, and

  ●         the “dead code” and “dead data” had to be completely removed from the source code (i.e. code and data that is never used in any possible operational state of the program).


Despite its advantages, the filtered source code distribution deprives a developer of the full set of possible uses for the initial source code (although a developer inclination to aim at a universal solution is deemed to extend the development period indefinitely). This is where custom ABCD Proto-Kernel™ distributions become attractive.

 

Note:   A custom distribution may include a limited license for the source code filtering utility. The developer organization may then meet the source code redistribution requirements (imposed by the GPL-style licensing) with the same strategy as CONNOTECH uses for the ABCD Proto-Kernel™. This would provide a close fit between the redistributed source code and the actual embedded system configuration. We do not claim the source code filtering to be a superior source code development procedure. It works for us, but a developer organization may have other procedures that are better suited for the situation it faces.


Custom Distributions of the ABCD Proto-Kernel™


There are many circumstances where a custom distributions of the ABCD Proto-Kernel™ software makes sense, e.g. for

  ●         kernel features that are not part of the website distribution,

  ●         specific embedded target system configurations,

  ●         support of additional peripherals, communications channels and/or protocols, and

  ●         support of other processors.


A custom distribution arrangement typically comes with installation support and other developer support services. This allows a faster learning curve and quicker bug fixes. At CONNOTECH, we believe that custom distributions of the ABCD Proto-Kernel™ software is the most efficient development strategy when time-to-market is important.


This type of software procurement strategy exhibits some characteristics of the embedded tool vendor offerings (tools packaging and integration, target compatibility, installation support), many benefits of free software (e.g. no usage-based licensing), and the customer dedication of consulting services.


We invite the interested parties to contact us about custom distribution requirements. The rates are reasonable, the value is great. The ABCD Proto-Kernel™ offering are unique.





[ CONNOTECH home page: http://www.connotech.com | e-mail to: info@connotech.com ]




CONNOTECH Experts-conseils Inc.

9130 Place de Montgolfier

Montréal, Québec, Canada, H2M 2A1

Tél.: +1-514-385-5691

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