Multimedia Cards

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I want to use a MSP430F149 as a controller for a datalogger,
and interface it with a variety of different sized MultiMediaCards.

Does anyone know whether any software examples, or even some
older specs for getting micros to talk to these devices, is available
on-line? The current spec is available from www.mmca.org for about
US$500.

Thanks
David.

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reply to

dmmilne at ozemail dot com dot au


Re: Multimedia Cards
The answer is it's either easy or hard. Email me offline and I'll provide
you with a published manufacturers MMC card datasheet that includes all of
what you need without having to purchase the spec. from MMCA.

If you want to use the embedded FAT16 filesystem, it can be quite a bit of
work. If you want to just store and retrieve data using 512-byte blocks,
it's really quite easy. An 8-pin PIC could do it.

Noel

snipped-for-privacy@home.now wrote:

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Re: Multimedia Cards
There is some C code for a Pic micro at:
www.bundu.com/download.html
This should be easy to port to another micro. It stores and retrieves
data in 512 byte blocks, however, as the previous poster pointed out,
if you need a FAT filesystem, you are looking at a lot of work.
Regards.

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Re: Multimedia Cards
Here is some references to MMC cards Rob pointed to me...I am not sure
whether
it contains sufficient information for a decent project...
http://www.sandisk.com/tech/product_man-main.asp

For a low sampling rate ADC, I guess SmartMedia is better candidate than
MMC...
SmartMedia allows direct I/O operation in 8-bits and pretty simple to use...

If you only write ADC samples to the flash in FAT files, I guess the amount
of work
is not that great...

Kelvin




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Re: Multimedia Cards
Yes, the MMC doc will be more then enough for read/write to MMC cards.

But,
I think you underestimate the work required to get FAT file systems
working.

Kelvin @ SG wrote:
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Re: Multimedia Cards
hamilton you could be true...I am only reading and I have not done any FAT
project yet.

In my app, it will be simple. SM has only one empty file, which I formatted
and copied in
Windows.

During initialization, my ARM reads page by page then searches for my
filename (make it short-form)
and calculates the file's starting address...this involves sime FAT thing...

During ADC, ARM saves the frame in RAM...then transfers it into the card and
closes the file...

Sounds simple enough...


Kelvin








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use...
amount



Re: Multimedia Cards
Well...correction...After reading an MMC datasheet...actually MMC is as
simple to use as SmartMedia though it is slower...

Kelvin



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use...
amount



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