Hello,
I would like to make an interruption of the DMA via NIOS II. I took the example from the NIOS II software Developper Handbook and added the three alt_irq commands in order to initialise, register and enable my interruption. My interruption is number 6 thus I wrote :
alt_u8 buffer[1024];
alt_dma_rxchan rx;
/* flag used to indicate the transaction is complete */
volatile int dma_complete = 0;
/* function that is called when the transaction completes */
void dma_done (void* handle, void* data)
{
dma_complete = 1;
}
int main(void)
{
alt_irq_init (VGA_BASE); // avec dans system.h :# define VGA_BASE 0x00008200
alt_irq_register (6,NULL, dma_done);
alt_irq_enable (6);
/* Obtain a handle for the device */
if ((rx = alt_dma_rxchan_open ("/dev/vga")) == NULL)
{
printf ("Error: failed to open device\n");
exit (1);
}
else
{
/* Post the receive request */
if (alt_dma_rxchan_prepare (rx, buffer, 1024, dma_done, NULL) < 0)
{
printf ("Error: failed to post receive request\n");
exit (1);
}
/* Wait for the transaction to complete */
while (!dma_complete);
printf ("Transaction complete\n");
alt_dma_rxchan_close (rx);
}
return 0;
}
Then, I have the following message on the console : "Error: failed to open device".
I am a newbie with NIOS II so maybe my mistake is huge. Could someone help me ?
Thank you very much, I am lost.
