Going back to the original post:

> This work is totally new for me, reason why i'm having some difficulties. 
> It
> consists in the using of a digital camera with 640 x 480 pixels resolution
> (VGA), that reads 30 frames per second. The microcontroller PIC24f is
> connected with a SD card where the data is stored.
> I ask if it is possible to record directly the data in the SD card or if 
> it
> is necessary a memory RAM connected to the microcontroller and what type?
> I really appreciate any clarification.

ASSUME
8 bits per pixel.
No compression (jped subsequently mentioned I think)

Data rate is 640 x 480 x 30 = 9.216 MBps
Bit rate is that x 8 = ~ 74 MbpsCard rates are specified in multiples of 130 
kbps for historical reasons.
74 Mbps/130000 = a 567X card.

That's a higher spec than anything I've ever seen fir ANY flash card, but 
perhaps not higher than I've seen announced as vapourware.

SDHC class 6 are the fastest adertised here at 6 MB/s or 48 Mbps.

In CF you get

Verbatim CF Card Pro Series 300x 8GB
SanDisk Extreme IV 266X CompactFlash 8GB

About half the above speed.

In your latest email you mention a JPEG module. If this is done 'on the fly' 
by the module then your data rate will be reduced to much reduced by JPEG 
and you would be able to use a top end SD card.

BUT then you mention IIC transfer.
That could cause "problems". At least.



          Russell McMahon





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