[Arm-netbook] EOMA/CF idea

[jonsmirl at gmail.com]

On Fri, Dec 30, 2011 at 11:45 AM, lkcl luke <luke.leighton at gmail.com> wrote:
> On Fri, Dec 30, 2011 at 3:13 PM, jonsmirl at gmail.com <jonsmirl at gmail.com> wrote:
>> On Fri, Dec 30, 2011 at 9:50 AM, Bari Ari <bari at onelabs.com> wrote:
>>> On 12/30/2011 08:32 AM, lkcl luke wrote:
>>>> http://elinux.org/Embedded_Open_Modular_Architecture/CompactFlash
>>>>
>>>> someone on slashdot mentioned "why not use Compact Flash?" and i went
>>>> "don't be silly, it's only got 44 pins" well it turns out that i was
>>>> wrong, it's 50.  that's enough... *if* you use LVDS not RGB/TTL.
>>>>
>>>> i think the tiny size is absolutely awesome, and well worth the
>>>> sacrifice of the limitations of LVDS.
>>>>
>>>> thoughts, anyone?
>>
>> All of these connectors are around $2 for the male and another $2 for
>> the female in 100K quantity. The main use of these connectors is
>> accessing the LCD controlle
>
>  10 RMB (appx $1.60) -
> http://item.taobao.com/item.htm?id=10700410631&cm_cat=0 that's for qty
> 1 from a random supplier.
>
>  i appreciate that that's just one random part, but pricing is
> different in china from europe and USA.
>
>
>> Alternatively you could mount a connector that will directly accept a
>> LCD cable like this one:
>> http://search.digikey.com/us/en/products/FH12-50S-0.5SH(55)/HFJ150CT-ND/1110390
>
>  that immediately restricts the product(s) to engineers, R&D and
> factory-installation only.
>
>  the EOMA standards are designed for mass-volume user-installation.
>
>> Then pick a range of LCDs with identical pinouts and set everything up
>> to work with them.
>> You need another similar connector for touch screens but it is much smaller.
>>
>> Now put everything else onto .1 header pins.
>
>  that is fine for engineers and factory-install.  it's been done
> already.  yuli magniel's OMAPMOD.  beagleboard etc.  rbpi. the list
> goes on.  the focus of EOMA is *mass-volume* products where the CPU
> card is swappable *by the user*, and swappable by the user *without
> risk of damage*.
>
>> Plan B - get rid of the LCD connector and just tell everyone to use HDMI.
>
>  naah.  some low-cost CPUs don't have HDMI.  that increases the price.
>  i don't know of a single SoC (at this mass-market level) which
> doesn't have RGB/TTL though.  with the exception of some of the
> marvell ones which have PCI-e instead.
>
>> Plan C - switch to SODIMM which is an edge connector. That eliminates
>> the cost of the male connector since it is fairly cheap to etch the
>> card fingers onto the PCB. Just make the SODIMM card longer, none of
>> the female connectors limit the card length.
>
>  jon, i believe you recommended SODIMM once before, a week or so ago.
> the reasoning has not changed during that time: i have not received
> any new input other than that which has already been covered.  i have
> already evaluated it and it is clearly and self-evidently unsuitable
> for mass-volume user-installation.
>
>  http://elinux.org/Embedded_Open_Modular_Architecture#SO-DIMM_form-factor
>
>  if however you can think of something that would make SODIMM suitable
> for mass-volume usage, for sale in hypermarkets where the product
> would not end up with 75% returns due to destruction by the average
> person because they broke it, i will be happy to change the evaluation
> and potential use-cases of SODIMM.

What is the application where the end user will want to swap CPU cards?




>
>  l.
>
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-- 
Jon Smirl
jonsmirl at gmail.com