Interface Overview
18-8
ADSP-BF50x Blackfin Processor Hardware Reference
In slave mode, the
SPI_FLG
bits have no effect, and each SPI uses the
SPISS
input as a slave select. Just as in the master mode case, the port pin
associated with
SPISS
must first be configured appropriately before use.
Figure 18-14 on page 18-38
shows the
SPI_FLG
register diagram.
Slave Select Inputs
If the SPI is in slave mode,
SPISS
acts as the slave select input. When
enabled as a master,
SPISS
can serve as an error detection input for the SPI
in a multimaster environment. The
PSSE
bit in
SPI_CTL
enables this fea-
ture. When
PSSE
= 1, the
SPISS
input is the master mode error input.
Otherwise,
SPISS
is ignored.
Use of FLS Bits in SPI_FLG for Multiple Slave SPI Systems
The FLSx bits in the SPI_FLG register are used in a multiple slave SPI
environment. For example, if there are eight SPI devices in the system
including a master processor equipped with seven slave selects, the master
processor can support the SPI mode transactions across the other seven
devices. This configuration requires only one master processor in this mul-
tislave environment. For example, assume that the SPI is the master. The
seven port pins that can be configured as SPI master mode slave-select
output pins can be connected to each of the slave SPI device’s SPISS pins.
In this configuration, the FLSx bits in SPI_FLG can be used in three
cases.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...