Hello,

I'm having problems implementig usage of the PDC on my AT91SAM9XE512 
evaluation board.

I learned, that the PDC is configured through control registers of the 
peripheral devices; like in the code below

1

    // write receive-buffer-address to receive-pointer-register

2

    *AT91C_SPI0_RPR = receive_buffer_address;

3

4

    // write buffer-size to receive-counter-register

5

    *AT91C_SPI0_RCR = receive_buffer_size;

6

7

    // enbale receive

8

    *AT91C_SPI0_PTCR = AT91C_PDC_RXTEN;

9

10

    // enbale transmit

11

    *AT91C_SPI0_PTCR = AT91C_PDC_TXTEN;

but i need to access the PDC directly to change specific channel or 
FIQ-configurations, which i can't do by simply changing these control 
registers.
How do I directly access and control the PDC and it's 
subsystems/controls in C (I am currently using IAR workbench)?

Please help. Thank you.