Problem with Chan's code 'ffsample'

Hello everybody,

I'm trying to implement the Chan's code in a ARM7 microcontroller, the LPC2368.

I can initialize the card but when I try to write some data nothing happens.
Apparently everything was allright becuse de bode gets the end of the writing function without any errors.

But I realized when I supposedly should enter in the ISR_MCI interrupt because of a 'flag' that indicates 'end block' it enters there because of an error 'TX Underrun'.
I imagine then that's the problem..

Have someone seen already this?

Leo