Datasheet

Table Of Contents
Advance Information MC68HC908GP20Rev 2.1
314 Freescale Semiconductor
20.14 I/O Registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .338
20.14.1 SPI Control Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . .338
20.14.2 SPI Status and Control Register . . . . . . . . . . . . . . . . . . . .340
20.14.3 SPI Data Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .343
20.2 Introduction
This section describes the serial peripheral interface (SPI) module,
which allows full-duplex, synchronous, serial communications with
peripheral devices.
20.3 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:
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
2
C (inter-integrated circuit) compatibility
I/O (input/output) port bit(s) software configurable with pullup
device(s) if configured as input port bit(s)