IOP/Core Interaction Options
7-16
ADSP-2126x SHARC Processor Hardware Reference
Listing 7-1. Chain Assignment
R0=0;
dm(CPx)=R0; /* clear CPx register */
R2=(TCB1+3) & 0x7FFFF; /* init DMA control registers and
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*/
Inserting a TCB in an Active Chain
This is supported by serial ports only. The SPI interface does not
support inserting a TCB in an active chain.
It is possible to insert a single DMA operation or another DMA chain
within an active DMA chain. Programs may need to perform insertion
when a high priority DMA requires service and cannot wait for the cur-
rent chain to finish.
When DMA on a channel is disabled and chaining on the channel is
enabled, the DMA channel is in chain insertion mode. This mode lets a
program insert a new DMA or DMA chain within the current chain with-
out effecting the current DMA transfer. Use the following sequence to
insert a DMA subchain for the serial port 0A channel while another chain
is active:
Содержание ADSP-21261 SHARC
Страница 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Страница 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Страница 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Страница 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Страница 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Страница 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...