Re: [Gumstix-users] Next Gen Gumstix

[Cliff L. B. <cl...@bi...>]

On Jul 5, 2006, at 8:22 PM, Craig Hughes wrote:
> We are thinking about daughtercard detection & identification.  Our
> upcoming dual-CF card has a CPLD on it (to handle the necessary
> switching between the CF slots),

*grin*  Good backwards-compatibility move.  I just dealt with a very  
similar "ultra-conservative massive serial bitstring" handshaking  
scheme in another field (hello, Acantostega).

I take it the CPLD, on that board, is primarily handling the  
multiplexing between the slots for select and addressing?  Last time  
I did a dual-PCMCIA interface for the PXA255 I remember it being  
pretty simple...

> 2. bit-banging instead of using something like I2C is more flexible,
> since for example, i2c isn't on the 92-pin side, and you don't
> necessarily want the fairly heavy-weight i2c subsystem to have to be
> loaded before you can do any other I/O

This is true.  (Though I'd argue that excluding I2C from the 92-pin  
connector was an oversight -- but that's because I'm an I2C geek.)

> And yes, we've started looking at FPGA on a 92-pin daughtercard.
> Actually, the main purpose for that would be to allow hanging a PCI
> bus off the 'stix with the PCI controller.

Ooooooh.  That would be entertaining.

Y'all still working on the PXA270-based board?  Last I heard it was  
RSN....

-Cliff L. Biffle