SPI Registers
10-36
ADSP-2126x SHARC Processor Hardware Reference
Use of DSxEN Bits in SPIFLG
for Multiple Slave SPI Systems
The
DSxEN
bits in the
SPIFLG
register are used in a multiple slave SPI envi-
ronment. For example, if there are five SPI devices in the system with an
ADSP-2126x master, then the master ADSP-2126x processor can support
the SPI mode transactions across all four other devices. This configuration
requires that only one ADSP-2126x be a master. For example, assume that
SPI0 is the master. The four flag pins on the ADSP-2126x master can be
connected to each of the slave SPI device’s
SPIDS
pins. In this configura-
tion, the
DSxEN
bits in the
SPIFLG
register can be used in three ways.
In cases 1 and 2, the processor acts as the master, and the four SPI micro-
controllers/peripherals act as slaves. In this configuration, the
ADSP-2126x processor can:
1. Transmit to all four SPI devices at the same time in Broadcast
mode. Here, all the
DSxEN
bits are set.
2. Receive and transmit from one SPI device by enabling only one
slave SPI device at a time.
In case 3, all five devices connected via SPI ports can be ADSP-2126x
processors.
3. If all the slaves are also ADSP-2126x processors, then the requestor
can receive data from only one ADSP-2126x processor (enable this
by setting the
DMISO
bit in the other slave processors) at a time and
transmit broadcast data to all four at the same time. This
DMISO
fea-
ture may be available in some other microcontrollers. Therefore, it
would be possible to use the
DMISO
feature with any other SPI
device which includes this functionality.
shows one ADSP-2126x processor as a master with three
ADSP-2126x processors (or other SPI-compatible devices) as slaves.
Summary of Contents for ADSP-21261 SHARC
Page 30: ...Contents xxx ADSP 2126x SHARC Processor Hardware Reference ...
Page 40: ...Register Diagram Conventions xl ADSP 2126x SHARC Processor Hardware Reference ...
Page 58: ...Differences From Previous SHARCs 1 18 ADSP 2126x SHARC Processor Hardware Reference ...
Page 112: ...Secondary Processing Element PEy 2 54 ADSP 2126x SHARC Processor Hardware Reference ...
Page 178: ...Summary 3 66 ADSP 2126x SHARC Processor Hardware Reference ...
Page 204: ...DAG Instruction Summary 4 26 ADSP 2126x SHARC Processor Hardware Reference ...
Page 322: ...Setting Up DMA 7 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 436: ...SPORT Programming Examples 9 86 ADSP 2126x SHARC Processor Hardware Reference ...
Page 521: ...ADSP 2126x SHARC Processor Hardware Reference 11 31 Input Data Port rts IDP_ISR end ...
Page 522: ...Input Data Port Programming Example 11 32 ADSP 2126x SHARC Processor Hardware Reference ...
Page 590: ...Timer Programming Examples 14 20 ADSP 2126x SHARC Processor Hardware Reference ...
Page 796: ...I O Processor Registers A 174 ADSP 2126x SHARC Processor Hardware Reference ...
Page 800: ...B 4 ADSP 2126x SHARC Processor Core Manual ...
Page 846: ...Index I 36 ADSP 2126x SHARC Processor Hardware Reference ...