Compact Flash size

Does anybody know what is the biggest CompactFlash disk one can use with the Altera NiosII 1c20 development board?

I was able to mount a 1GByte CompactFlash disk as /dev/cfa/1, but I can not write more than 500MBytes to it. If I try to write more data to it, it indicates that the disk is full, when in reality there is still more room available.

It does not mount if I try /dev/cfa/0.