Problems with read transfer

[Altera_Forum]

I have connect a simple read-write- component in my system. When i do a read transfer, i only get the hexidecimal value ffffffff and i don't know why. 

 ... unsigned long read; read = IORD_32Direct(SIMPLE_RW_0_base,0); ...

[Altera_Forum]

I think that when you have low active signal (as you did for the read and write enable signals), you need to end their name with _n instead of just n. If SOPC builder doesn't see the _n in the name, it will assume that they are active high signals. 

Either rename then with something that ends with _n or use them as active high signals in your code.