I use the EVK 1104 Kit and sd card interface in 4 bit mode Studio 5.1 and ASF2.11.1 USB mass storage example as base project.
I want to write large files max 2Gb on Sandisk ULTRA II cards.
In USB mass storage mode I can write files on SD at 5Mb/s.
Using the fat library and 4K buffer the top speed is 278Kb/s.
What's the difference?
I tried to use a preserve shown in AVR114 application note it took 44s for 40Mb it's to slow for me.
I need to write >1Mb/s
Any Ideas whats the difference between the two access modes?