[Arm-netbook] [EOMA26] example product layout

[joem]

On Mon, 2013-08-19 at 11:00 +0100, luke.leighton wrote:
> On Mon, Aug 19, 2013 at 9:35 AM, joem <joem at martindale-electric.co.uk> wrote:
> > On Mon, 2013-08-19 at 08:07 +0000, joem wrote:
> >> > does anyone know of any other SoCs that would suit EOMA-26?  i've
> >> > listed the TI AM3389 already
> >> > http://elinux.org/Embedded_Open_Modular_Architecture/EOMA-26
> >
> >
> > Sqeeeeeeek!!!
> >
> > This type of IO expander scheme chips are a waste of money for the
> > price they are being sold in relation to the much higher functions
> > that are expected of them.
> >
> > Its cheaper to get a $2 cortex-3 lets say with 48 pins or 64 pins
> > and then use its i2c to talk to the chip, and then have inside
> > the chip a little bit of software for keyboarding, led driving,
> > interrupt generation, adc, usb, ethernet, lcd, etc.
> 
>  yes - i mention that further down.
> 

Sorry, yes, I were trawling through list of datasheets and didn't get to
bottom of page. 

So would it not be easier to start with an arm cortex m3 lets say
and stick with it. The shipping cost would not pay for the difference
between a $2 chip and a $0.5 chip. Such an expansion board would cost
under $10 but do far more than anything competing with it.

There is also the LPC1768 costing $5
http://www.aliexpress.com/item/LPC1768FBD100-LPC1768-NXP-QFP100-100-brand-new-original-authentic/990248235.html
That has 100 pins, the Code Red eclipse IDE runs on Linux and is free up
to 128K, That could do a lot of damage to attack industrial strength
problems and still come in under $10 for a finished industrial strength
generic IO board.

I got KiCAD boards that I make already - the SoM1 CPU board takes 2
of these puppies and brings them out to 200 pin SODIMM.
http://www.gplsquared.com/SoM1/SoM1.html (the chip it takes is
marked up as LPC1764 - same pinout more memory in LPC1768 - 512K!)
It will take next to no time to modify it and make it specific for
EOMA26 needs.