[En-Nut-Discussion] shot filenames in nut- PHAT fs

[Harald Kipp]

Ole Reinhardt wrote:

>> ps: we got SD-HC cards working for writing as well now. Not sure how to
>> commit the changes.....
> 
> You could send me a patch if you like. At least me, I'm interested in
> it. I would then check in the patch into the development tree.

I also made some changes in at91_mci.c, as this doesn't seem to work at 
all. Unfortunately the AT91 MCI doesn't support SPI mode, so I had to 
figure out the differences between SD-Card and MMC initialization. So 
far, SDHC and SDIO are not working with this driver. I assume, that more 
had to be done than just modify the initialization.

I'm currently very, very busy on another project and won't be able to 
spend more time on this before next week.

Btw. Atmel will present our MCI driver on the Arm Dev Conference in 
Santa Clara next week. They run a small application on the 
AT91SAM9260-EK to demonstrate the impact of PDC (Atmel's DMA). Nut/OS 
reads MP3 files from an SD Card, decodes them by using the Helix 
software decoder and passes the PCM samples via I2S to an audio DAC. 
Without SSC PDC, Nut/OS has to handle nearly 90,000 IRQs per second and 
fails to keep up. With SSC PDC, the interrupt rate is reduced to less 
than 40 per second and the Nut/OS idle thread takes over the CPU most of 
the time.

Harald