Monthly Archives: December 2011

The Five Orders of Ignorance

Glennan Carnie

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.

Latest posts by Glennan Carnie (see all)

It’s not often you read a paper that has something unique and fresh to say about a topic, and expresses it in a clear and concise way.

Somehow, Phillip Armour’s The Five Orders of Ignorance had eluded me, until I found it referenced in another paper.

It really is an interesting point of view on software development.  You can read the paper here.

Armour’s central tenet is software is a mechanism for capturing knowledge. That is, (correct) software is the result of having […]

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Overcoming Name Clashes in Multiple C++ Interfaces

Niall Cooling

Director at Feabhas Limited
Co-Founder and Director of Feabhas since 1995.
Niall has been designing and programming embedded systems for over 30 years. He has worked in different sectors, including aerospace, telecomms, government and banking.
His current interest lie in IoT Security and Agile for Embedded Systems.

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Interfaces

One of our key design goals is to reduce coupling between objects and classes. By keeping coupling to a minimum a design is more resilient to change imposed by new feature requests or missing requirements[1].

An Interface represents an abstract service. That is, it is the specification of a set of behaviours (operations) that represent a problem that needs to be solved.

An Interface is more than a set of cohesive operations. The Interface can be thought of as a contract […]

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Effective Testing: The “Swiss Cheese” model

Glennan Carnie

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.

Latest posts by Glennan Carnie (see all)

Why do we test?

Software development is a collaborative effort. You bring in input from customers, managers, developers, and QA and synthesize a result. You do this because mistakes in requirements or architecture are expensive, possibly leading to lost sales.

When we develop products we want them to be successful. We want our customers to buy, enjoy, and recommend our products or services. In other words, we want to build quality products. In this case, quality means four inter-related things:

Compliance quality– Can […]

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More appalling user interface design

Glennan Carnie

Technical Consultant at Feabhas Ltd
Glennan is an embedded systems and software engineer with over 20 years experience, mostly in high-integrity systems for the defence and aerospace industry.

He specialises in C++, UML, software modelling, Systems Engineering and process development.

Latest posts by Glennan Carnie (see all)

I came across a wonderfully counter-intuitive piece of user interface design this week.

The room I was in had a sliding shutter (that, for reasons best known to the architects, opened into the main building and not outside).  The two halves of the shutter are controlled independently – that is, you can close one side or the other, or both.  Each shutter is controlled with independent switch panels.

Common sense would suggest a single rocker switch: pushing one side would close the […]

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