Lpc2000

"Rick Collins" <gnuarm@...> writes:

> Would you mind posting this info to the armForth group here at Yahoo!
> as well?  As far as I can tell your forth is the only one that is
> actually available for ARM chips that are in use today.  

Ok, I just posted it there.

> I have a Cogent board with an OKI ARM chip that I am not using.
 ...
>   I would be happy to lend it to you.  

Thank you.  Let's keep it in mind for the future, but right now I have
too much to do with just the development systems already frowning at me
from the shelves, tapping their feet, saying "C'mon, c'mon, get to work.
Stop playing FreeCell."  If I could just get them to stop tapping their
feet ... that's the worst of it.
 
> As long as I am on the topic, you can get some nice hardware for a
> song by buying a router.

I like that idea, also the Game Boy Advance and/or one of the ARM-based
Palm Pilots (they will always be "Palm Pilots" to me).

However, for ease of development, I couldn't be happier than with the
Olimex LPC2106 board I'm using.

I have that board wired up to both an MMC socket (as in the pictures on
my web site) and an SD socket.  I can read and write MMC disks in either
socket and read and write SD disks in the SD socket.  In all cases, I am
using SPI mode, using the LPC's built-in SPI.  

With either an MMC disk or an SD disk, I am seeing a time of
approximately 78 MS to read a 512-byte sector.  I think a substantial
amount of that time is a delay internal to the card, rather than related
to the LPC.  I had hoped that the SD disk, even in MMC/SPI mode, would
be faster that the MMC disk, but it doesn't seem to be.

My next step in that direction, probably, is to wire an SD socket to
another Olimex board, using GPIO rather than the built-in SPI, and work
out talking to the disk using 4 data lines rather than just the one used
in SPI mode.  However, if the bulk of the time is spent internally in
the disk, I may not see the speedup I hope for.

I want the advantages of CompactFlash disk speed, with the far narrower
interface of an MMC or SD disk.


-- 
Frank