Advance Information MC68HC908MR16/MC68HC908MR32 — Rev. 4.0
248 Serial Peripheral Interface Module (SPI) MOTOROLA
Serial Peripheral Interface Module (SPI)
13.2 Introduction
The serial peripheral interface (SPI) module allows ful l -duplex,
synchronous, serial communications with peripheral devices.
13.3 Features
Features of the SPI module include:
Full-duplex operation
Master and slave modes
Double-buffered operation with separate transmit and receive
registers
Four master mode frequencies (maximum = bus frequency ÷2)
Maximum slave mode frequency = bus frequency
Serial clock with programmable polarity and phase
Two separately enabled interrupts with central processor unit
(CPU) service:
SPRF (SPI receiver full)
SPTE (SPI transmitter empty)
Mode fault error flag with CPU interrupt capability
Overflow error flag with CPU interrupt capability
Programmable wired-OR mode
•I
2C (inter-integrated circuit) compatibility
13.4 Pin Name Conventions
The generic names of the SPI input/output (I/O) pins are:
•SS, slave select
SPSCK, SPI serial clock
MOSI, master out/slave in
MISO, master in/slave out