Hello,
my goal is to transfer via WiFi a 1Gbyte file to an SD Card.
I need to do this transfer in the shortest time possible (4 MByte/s or more would be ok).
Have you got any suggestions? I've never used AT91 so I'm thinking about buying an evaluation board. What data rate can I expect from AT91?
Thank you in advance.
Best regards,
Marco

Which AT91 part? The family runs the gambit from ARM7, ARM9 to Cortex-M3.

Have you experience with WiFi modules, SD Card interfacing, and file systems? Have you coded a prototype on a PC, and tried different SD card sizes/brands? What speed to you see there? How's that impacted by network traffic, and proximity to the access-point?

Do you need SDHC to achieve your goal.

Hello CptTitanic,
thanks for your reply.
Until now I've always worked with Microchip. I have developed a card based on a MRF24WB0MA (wifi interface with 2Mbit/s speed), and another with an SD Card with a FAT16 filesystem.
Now I can't simply merge these two since the speed would be too low for this new project. Also, I need to use SDHC cards.

So now I could accomplish the goal but the transfer rate would be too low.
At the moment the bottle neck is the WIFI receiver but the speed to the SD Card is also slow.
So I would like to get an idea of the transfer rate I would get with an AT91-based system, it does not matter which at91 part. Just want to understand if AT91 is the good direction I have to take.

Thanks again.
Best regards,
Marco

Hi
This speed is possible but not in SPI mode. 4MB/s is possible in 4 bit data mode using multi-block writing. This interface is only a domain of the at91sam9 processors. I have ready procedures for these processors.
I'd recommend the at91sam9xe512 to start with. I has embedded FLASH memory and the aforementioned SD interface. Look at: http://www.atmel.com/Images/6254s.pdf