I am trying to get some profiling numbers for our upcoming project. I have connected a Class 6 SD Card to K60 eval board. The low level read access is very slow. Current rate for reading just a sector (512 bytes) is about 800 KB/s.
I changed the baud rate clock and this does NOT seem to affect read access. I get approximately same number for 4000000 and 25000000.
The low level read function _esdhc_read reads 4 bytes and then waits to check some status. This does not seem to be the most efficient way. How can I improve the performance?