Datasheet

dsPIC33F

7.4 DMA Initialization Example

The following is a DMA initialization example:

EXAMPLE 7-1: DMA SAMPLE INITIALIZATION METHOD

// Clear all DMA controller status bits to a known state

DMACS0 = 0;

// Set up DMA Channel 0: Word mode, Read from Peripheral & Write to DMA; Interrupt when all the

data has been moved; Indirect with post-increment; Continuous mode with Ping-Pong Disabled

DMA0CON = 0x0000;

//Automatic DMA transfer initiation by DMA request; DMA Peripheral IRQ Number set up for ADC1

DMA0REQ = 0x000D;

// Set up offset into DMA RAM so that the buffer that collects ADC result data starts at the base

of DMA RAM

DMA0STA = 0x0000;

// DMA0PAD should be loaded with the address of the ADC conversion result register

DMA0PAD = (volatile unsigned int) &ADC1BUF0;

// DMA transfer of 256 words of data

DMA0CNT = 0x0100 ;

//Clear the DMA0 Interrupt Flag

IFS0bits.DMA0IF = 0;

//Enable DMA0 Interrupts

IEC0bits.DMA0IE = 1;

//Enable the DMA0 Channel

DMA0CONbits.CHEN = 1;