FIFO to Memory Data Transfer
11-16
ADSP-2126x SHARC Processor Hardware Reference
• Eight dedicated DMA channels can sort and transfer the data into
one buffer per source channel. When the memory buffer is full, the
DMA channel raises an interrupt in the DAI Interrupt Controller.
This method of moving data from the IDP FIFO is described in
Interrupt-Driven Transfers
The output of the FIFO can be directly fetched by reading from the
IDP_FIFO
register. The
IDP_FIFO
register is used only to read and remove
the top sample from the FIFO, which is eight locations deep.
As data is read from the
IDP_FIFO
register, it is removed from the FIFO
and new data is copied into the
IDP_FIFO
register. The contents of the
IDP_NSET
bits (bits 3–0 in the
IDP_CTL
register) represent a threshold
number of entries (
N
) in the FIFO. When the FIFO fills to a point where
it has more than
N
words (data in FIFO exceeds the value set in the
IDP_NSET
bit field, bits 3–0 of
IDP_CTL
register), a DAI interrupt is gener-
ated. This DAI interrupt corresponds to the
IDP_FIFO_GTN_INT
bit, the
eighth interrupt in
DAI_IRPTL_L
or
DAI_IRPTL_H
. The core can use this
interrupt to detect when data needs to be read.
Starting an Interrupt-Driven Transfer
To start an interrupt-driven transfer:
1. Clear and halt FIFO by setting (= 1) and clearing (= 0) the
IDP_EN-
ABLE
bit (bit 7 in the
IDP_CTL
register).
2. Set the required values for:
•
IDP_SMODEx
bits in the
IDP_CTL
register to specify the frame
sync format for the serial inputs (I
2
S, Left-justified Sample
Pair, or Right-justified Sample Pair Mode).
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 ...