Analog Devices ADSP-BF59x Blackfin, Hardware Reference Manual, Page: 578 / 772

Programming Examples
14-72 ADSP-BF59x Blackfin Processor Hardware Reference
BITSET(R0,0); /* R0 still contains value of CONFIG register -
set bit 0 */
W[P0] = R0; /* enable DMA channel (SPORT not enabled yet) */
Interrupt Servicing
The receive channel and the transmit channel will each generate an inter-
rupt request if so programmed. The following code fragments show the
minimum actions that must be taken. Not shown is the programming of
the core and system event controllers.
Listing 14-3. Servicing an Interrupt
RECEIVE_ISR:
[--SP] = RETI; /* nesting of interrupts */
/* clear DMA interrupt request */
P0.h = hi(DMA3_IRQ_STATUS);
P0.l = lo(DMA3_IRQ_STATUS);
R1 = 1;
W[P0] = R1.l; /* write one to clear */
RETI = [SP++];
rti;
TRANSMIT_ISR:
[--SP] = RETI; /* nesting of interrupts */
/* clear DMA interrupt request */
P0.h = hi(DMA4_IRQ_STATUS);
P0.l = lo(DMA4_IRQ_STATUS);
R1 = 1;
W[P0] = R1.l; /* write one to clear */
RETI = [SP++];
rti;