IORD 11.0 vs IORD 9.1

Hello,

Code:

--- Quote Start ---

int main()

{

int i;

while(1)

{

i = IORD_ALTERA_AVALON_PIO_EDGE_CAP(BUTTON_BASE);

printf("PIO EDGE CAP: %d\n", i);

IOWR_ALTERA_AVALON_PIO_EDGE_CAP(BUTTON_BASE, 0x0);

usleep(1000000);

}

}

--- Quote End ---

BUTTON is a 4-bit PIO in my SOPC.

If I run this code with Nios II 9.1 I read: PIO EDGE CAP: 0

If I press BUTTON[0] I read: PIO EDGE CAP: 1

..

If I press BUTTON[3] I read: PIO EDGE CAP: 8

Now:

If I run the same code with Nios II 11.0 I read: PIO EDGE CAP: 512

If I press BUTTON[0] I read: PIO EDGE CAP: 513

..

If I press BUTTON[3] I read: PIO EDGE CAP: 520

What does it means?

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