Craig Hughes wrote:
> On Feb 26, 2007, at 8:19 AM, John Rudd wrote:
>> 1) There's a Net-MMC board, so why not a Wifistix-MMC board (like the
>> wifistix-cf, only remove the CF slot and replace it with an MMC slot).
> Because the wifi module is connected to the CF controller, and CF and
> MMC are mututally exclusive on the PXA255.
Does that mean that you could, in theory, make an expansion board with 2
Why not do that? (and, if that IS the case, why does the cfstix only
have one CF slot?)
And, while we're there, PCMCIA/PC-Card is supposed to be identical to
CF, just in different form factors and connector size/layout. The
problem is that while lots of people make a PCMCIA card that will hold a
CF card (making every laptop capable of using CF cards) ... I've only
found one device that lets you put a PCMCIA card into a CF slot, and it
only works with 16 bit PCMCIA cards, and not 32 bit ones.
Plus, the CF slot faces off the side of the expansion board. That makes
sense for a CF card, but if you're trying to hang a CF->PCMCIA adapter,
and then an entire PCMCIA card, off of the side of the Gumstix then
takes up a ton of room ...
My first several board suggestions were based on looking at what was
offered and what was missing from that. Having taken more time, looking
at the three projects I want to do, and what it would take to make them
happen, I can boil this down to two boards I specifically want to utilize:
1) cfstix-2 : a gumstix expansion with 2 CF slots. The ability to have
BOTH a CF hard drive for an extended OS install, AND a CF card for other
uses is MUCH more flexible than forcing everyone to choose between
storage OR flexible peripheral selection (or project specific
peripherals). I don't propose deleting the cfstix from the offerings
though, as the slowly lower profile of just one cf slot might appeal to
2) a gumstix board that starts with the cfstix-2 idea, turns the
connector side ways, and replaces it with a PCMCIA card holder (2
slots). So, in the end, you'll have a PCMCIA card that runs parallel to
the gumstix, and covers the gumstix boards (ie. don't arrange it to
stick out the other side, like the way the tweener board sticks out).
Sure, PCMCIA cards are HUGE compared to gumstix boards ... but they
offer a type and range of flexibility that doesn't come with other,
similar, embedded expansion boards. Further, the CF market seems to be
getting smaller and smaller lately.
3) Variations might be nice. A board with 1 PCMCIA slot (for reduced
profile, not to replace the other slot with another capability). Or a
board that has 1 CF card slot and one PCMCIA card slot (you could easily
accomplish this with item #2 above, using an adapter, but I've seen a
few PC-104 boards that do this, so it might be useful here).
And, of course, knowing when verdex is going to be available would be
nice too. Two of the projects I want to work on will need USB host
capability. Trying to accomplish that via CF->PCMCIA adapter with a
PCMCIA USB card plugged into it makes for a HUGE footprint that I don't
otherwise need to have. Further, it may not actually work because I
don't know if the PCMCIA USB card is 16 bit or 32 bit.
What I think I actually need for my projects are:
A) Essentially, a pocket, battery powered, version of the Globesurfer II
7.2, from Option Wireless Technology.
* USB host (and maybe USB client)
* Two PCMCIA slots OR 1 PCMCIA slot and one CF slot. (2 PCMCIA would
be better, though)
B) A Linux PDA, similar in concept to the Sony Mylo and Nokia N800.
* USB client
* USB host
* some form of storage (pref. not via the USB host, nor bluetooth)
* Either a CF slot or a PCMCIA slot (pref. PCMCIA)
C) Purely a lark, based on the original star trek tricorder.
* a usable CF slot (could be PCMCIA, but CF is actually better)
(there's a company that makes a wide range of CF cards that are
* two storage devices (one could be USB host, but I'd prefer CF)
(why 2? one for a larger OS install to hold programs and drivers
around the array of swappable sensors, and one to be removable
for recording the data the sensors collect)
I suppose I could do a preliminary version of the PDA project, without
USB Host and using Bluetooth for communication (for network access
and/or storage)... but, I can't really do what I want using Gumstix
until I have at least USB Host.