Page Fault Exception problem

[Almamu]

I'm trying to support ATA and ATAPI drivers in my OS, but when i do this:

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//set up Device Control register
pio_outbyte( CB_DC, dc );

it gives a Page Fault Exceptions, and halts...
definitions of dc and CB_DC:

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#define CB_DC 8
//In the same function that the pio_outbyte error:
unsigned char dc;
//setup registry values:
dc = (unsigned char) ( int_use_intr_flag ? 0 : CB_DC_NIEN );

pio_outbyte:

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static void pio_outbyte( int addr, unsigned char data )
{
   //!!! write an 8-bit ATA register
   * pio_reg_addrs[ addr ] = data;
}

Any idea ?

[Combuster]

Do you know the difference between PIO and MMIO? Your source doesn't.

[Almamu]

Do you know the difference between PIO and MMIO? Your source doesn't.

Im only using PIO only to test it and try to code a working driver...

[NickJohnson]

Here's a hint: the x86 has separate PIO and memory/MMIO address spaces. Pointers are for one of them: can you guess which?

[Almamu]

Here's a hint: the x86 has separate PIO and memory/MMIO address spaces. Pointers are for one of them: can you guess which?

I think i haven't understanded the question, but i guess it's PIO

[Combuster]

Don't think. Know.