EZ80F91MCU Datasheet, PDF (228/396 Pages) Zilog, Inc. – eZ80Acclaim-TM Flash Microcontrollers

eZ80F91 MCU
Product Specification
209
Serial Peripheral Interface
The Serial Peripheral Interface (SPI) is a synchronous interface allowing several
SPI-type devices to be interconnected. The SPI is a full-duplex, synchronous,
character-oriented communication channel that employs a four-wire interface. The
SPI block consists of a transmitter, receiver, baud rate generator, and control unit.
During an SPI transfer, data is sent and received simultaneously by both the mas-
ter and the slave SPI devices.
In a serial peripheral interface, separate signals are required for data and clock.
The SPI can be configured as either a master or a slave. The connection of two
SPI devices (one master and one slave) and the direction of data transfer is dem-
onstrated in Figures 39 and 40 .
DATAIN
SS
MISO
MASTER
Bit 0
Bit 7
8-Bit Shift Register
SCK
DATAOUT
CLKOUT
Baud Rate
Generator
Figure 39. SPI Master Device
ENABLE
SS
SLAVE
DATAIN
CLKIN
MOSI
SCK
Bit 0
Bit 7
8-Bit Shift Register
Figure 40. SPI Slave Device
MISO
DATAOUT
PS019209-0504
PRELIMINARY
Serial Peripheral Interface