user6856: I keep reading how Arduinos are "open source", but my understanding of OSH is that all its components must be open source.
Arduino uses an Atmel 8-bit CPU - but Googling this shows the Atmel is proprietary!?
So I ask: how can Arduino be OSH if it's chief component - its Atmel CPU - is proprietary?!?

user313: I just scanned over the TAPR and CERN open hardware licenses and I didn't see such a provision. My quick take on OHLs is that they are specifications for building the hardware - and therefore, information - not the hardware itself. And it only makes sense when we consider the incredibly expensive and complicated (from an experimenter's point of view) infrastructure that is a chip foundry necessary to create the kinds of hardware we take for granted and have reduced to commodity parts, CPUs, & MCUs being a prime example.
Thus "Arduino" is an open source specification for building microcontroller boards or board-sets based on ATMEL MCU chips, as well as the products of the Italian company SmartProjects. That is why there are so-called Arduino clones, otherwise, why wouldn't any clone of an Arduino be an Arduino?

6856: <p>I keep reading how Arduinos are "open source", but my understanding of OSH is that all its components must be open source.</p>

<p>Arduino uses an Atmel 8-bit CPU - but Googling this shows the Atmel is proprietary!?</p>

<p>So I ask: how can Arduino be OSH if it's chief component - its Atmel CPU - is proprietary?!?</p>
 313: <p>I just scanned over the <a href="http://en.wikipedia.org/wiki/TAPR_Open_Hardware_License#Conditions" rel="nofollow">TAPR</a> and <a href="http://www.ohwr.org/documents/294" rel="nofollow">CERN</a> open hardware licenses and I didn't see such a provision. My quick take on OHLs is that they are specifications for building the hardware - and therefore, information - not the hardware itself. And it only makes sense when we consider the incredibly expensive and complicated (from an experimenter's point of view) infrastructure that is a chip foundry necessary to create the kinds of hardware we take for granted and have reduced to commodity parts, CPUs, &amp; MCUs being a prime example.</p>

<p>Thus "Arduino" is an open source specification for building microcontroller boards or board-sets based on ATMEL MCU chips, as well as the products of the Italian company SmartProjects. That is why there are so-called Arduino clones, otherwise, why wouldn't any clone of an Arduino <em>be</em> an Arduino?</p>
