Maybe there is some rom-space left to add some functions as "swapping"
memory pages from a defined size (e.g. 16k) from-and-to compact flash using
the new interface.

LD DE,%aabbbbbb
CALL SWAPCF

aa = select memory page:
00 - 0000-3fff
01 - 4000-7fff
10 - 8000-afff
11 - b000-efff

bb = block on disk (maximum of 10 million logical blocks)

Use a fixed 'block' for the space to swap to on disk, e.g. block 0.

So SWAPCF does:
  SAVE MEMORY PAGE aa TO BLOCK 0
  LOAD BLOCK bbbbbb TO MEMORY PAGE aa


Just an idea...

Rom 4.0 ?


Ben

> -----Oorspronkelijk bericht-----
> Van: [EMAIL PROTECTED]
> [mailto:[EMAIL PROTECTED] Edwin Blink
> Verzonden: dinsdag 29 juni 2004 12:41
> Aan: [EMAIL PROTECTED]
> Onderwerp: Re: A poor mans CF interface :-)
> 
> 
> 
> From: "Stuart Brady" <[EMAIL PROTECTED]>
> 
> > This looks great! I'm especially interested in this, since 
> I only have a
> > single 1 meg card. I have a few questions, though:
> 
> > Is this just as fast as the SAM's internal memory? (I don't 
> know whether
> > or not the 1 meg card is slower.) Also, how expensive is paging?
> 
> The CF will not work just like RAM instead it works just like a 8-bit
> harddisk
> by using memory mapped I/O. Every 512 byte sector must be 
> selected first.
> But when selected and available it will be as fast as RAM an 
> can be loaded
> with a single LDIR
> instruction or in any other way you like. It's also possible 
> to execute code
> from it directly.
>  But only in a linair way.
> 
> > (I will need to do paging every few instructions, since I'm mainly
> > interested in using CF as extra memory, rather than as disk space.)
> 
> I hope your not to disapointed now.
> 
> 
> Edwin
> 


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