ADSP-BF50x Blackfin Processor Hardware Reference
18-5
SPI-Compatible Port Controller
SPI Clock Signal (SCK)
The
SCK
signal is the serial clock signal. This control signal is driven by the
master and controls the rate at which data is transferred. The master may
transmit data at a variety of bit rates. The
SCK
signal cycles once for each
bit transmitted. It is an output signal if the device is configured as a mas-
ter, and an input signal if the device is configured as a slave.
The
SCK
is a gated clock that is active during data transfers only for the
length of the transferred word. The number of active clock edges is equal
to the number of bits driven on the data lines. Slave devices ignore the
serial clock if the
SPISS
input is driven inactive (high).
The
SCK
is used to shift out and shift in the data driven on the
MISO
and
MOSI
lines. Clock polarity and clock phase relative to data are programma-
ble in the
SPI_CTL
register and define the transfer format.
Master-Out, Slave-In (MOSI) Signal
The master-out, slave-in (
MOSI
) signal is one of the bidirectional I/O data
pins. If the processor is configured as a master, the
MOSI
pin transmits data
out. If the processor is configured as a slave, the
MOSI
pin receives data in.
In an SPI interconnection, the data is shifted out from the
MOSI
output
pin of the master and shifted into the
MOSI
input(s) of the slave(s).
Master-In, Slave-Out (MISO) Signal
The master-in, slave-out (
MISO
) signal is one of the bidirectional I/O data
pins. If the processor is configured as a master, the
MISO
pin receives data
in. If the processor is configured as a slave, the
MISO
pin transmits data
out. In an SPI interconnection, the data is shifted out from the
MISO
out-
put pin of the slave and shifted into the
MISO
input pin of the master.
Only one slave is allowed to transmit data at any given time.
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 ...