[Arm-netbook] Interchangeable screen

[Luke Kenneth Casson Leighton]

On Wed, Sep 16, 2015 at 1:41 PM, GaCuest <gacuest at gmail.com> wrote:
> Well, we are designing a handheld games console based on EOMA-68.

 yay!  (and yes, paul, this one:
http://rhombus-tech.net/community_ideas/games_console/ )

> We have thought about doing an interchangeable screen. Users can buy the handheld games console without a display (more cheaper, users can use the HDMI of EOMA-68), with a 480p display or 720p display (more expensive) and upgrade it in a future. We would connect the TFT and touch screen connector on a PCB, and user may connect it with a connector to the base PCB.
>
> We have thought about use neodymium magnet (some of 2x1 mm of them) to connect the case of the display+touch panel with the case of handheld games console. But we have some doubts about how to connect both PCB.
>
> We've thought use a slim B2B connector like this: http://www.literature.molex.com/SQLImages/kelmscott/Molex/PDF_Images/987651-2331.PDF
>
> The problem is that slim B2B connector have slow mating cycles (about 30-50 times). Any can help us about a better way to connect it?

 honestly, i don't recommend letting users consider it to be an
"end-user arbitrarily replaceable" component, but more of an "end user
*serviceable*" part i.e. they definitely definitely need some sort of
technical skill.

 encouraging that view by requiring that they use a screwdriver or
other tool to get at the screen would, i feel, be something that you
should deliberately push users towards so that they feel uncomfortable
unless they are confident with tools and ESD precautions.

if the screen could be packaged in a small self-contained unit that
had absolutely no chance of physical damage, where it was possible to
"slot in" to a special set of guide rails where there was absolutely
no chance that the end user could possibly get it wrong, then i would
say "go for it".

 however i think you'd agree that doing so hugely complicates the
casework design and leaves you with a lot more to consider right now.

 my advice to you therefore would be to use an FPC cable at either end
and to have the LCD module screwed down, deliberately so that it's
clear that this is *absolutely not* something that you should expect a
3-year-old or a 90-year-old infirm and elderly non-technical person to
be able to handle.

 once you have a first revision out the door, and have some cashflow,
by all means come back to the end-user removable LCD concept, but
right now i think you're asking too much.

l.