Operating Modes
2-34
ADSP-214xx SHARC Processor Hardware Reference
Listing 2-1. Chain Assignment
R0=0;
dm(CPx)=R0;
/* clear CPx register */
/* init DMA control registers */
R2=(TCB1+3) & 0x7FFFF;
/* load IIx address of next TCB
and mask address */
R2=bset R2 by 19;
/* set PCI bit */
dm(TCB2)=R2;
/* write address to CPx location of
current TCB */
R2=(TCB2+3) & 0x7FFFF;
/* load IIx address of next TCB and
mask address*/
R2=bclr R2 by 19;
/* clear PCI bit */
dm(TCB1)=R2;
/* write address to CPx location of
current TCB */
dm(CPx)=R2;
/* write IIx address of TCB1 to CPx
register to start chaining*/
Chained DMA operations may only occur within the same chan-
nel. The processor does not support cross-channel chaining.
Starting Chain Loading
A DMA sequence is defined as the sum of the DMA transfers for a single
channel, from when the parameter registers initialize to when the count
register decrements to zero. Each DMA channel has a chaining enable bit
(
CHEN
) in the corresponding control register.
To start the chain, write the internal index address of the first TCB to the
chain pointer register. When chaining is enabled, DMA transfers are initi-
ated by writing a memory address to the chain pointer register. This is also
an easy way to start a single DMA sequence, with no subsequent chained
DMAs.
www.BDTIC.com/ADI
Содержание SHARC ADSP-214 Series
Страница 60: ...Contents lx ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 72: ...Notation Conventions lxxii ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 130: ...Programming Model 2 52 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 264: ...Programming Models 3 134 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 290: ...Programming Model 4 26 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 296: ...Programming Model 5 6 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 396: ...Effect Latency 7 28 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 520: ...Programming Model 10 62 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 616: ...Debug Features 14 22 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 656: ...Programming Model 15 40 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 714: ...Programming Model 19 10 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1132: ...Register Listing A 306 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...
Страница 1192: ...Index I 34 ADSP 214xx SHARC Processor Hardware Reference www BDTIC com ADI...