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
// write receive-buffer-address to receive-pointer-register *AT91C_SPI0_RPR = receive_buffer_address; // write buffer-size to receive-counter-register *AT91C_SPI0_RCR = receive_buffer_size; // enbale receive *AT91C_SPI0_PTCR = AT91C_PDC_RXTEN; // enbale transmit *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.