[Arm-netbook] EOMA/CF idea

[lkcl luke]

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.

 l.