MC9S08DZ16 FREESCALE [Freescale Semiconductor, Inc], MC9S08DZ16 Datasheet - Page 278

• Manufacturer Part Number: MC9S08DZ16
• Description: 8-Bit HCS08 Central Processor Unit (CPU)
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Chapter 13 Serial Peripheral Interface (S08SPIV3)
13.2
The SPI optionally shares four port pins. The function of these pins depends on the settings of SPI control
bits. When the SPI is disabled (SPE = 0), these four pins revert to being general-purpose port I/O pins that
are not controlled by the SPI.
13.2.1
When the SPI is enabled as a slave, this pin is the serial clock input. When the SPI is enabled as a master,
this pin is the serial clock output.
13.2.2
When the SPI is enabled as a master and SPI pin control zero (SPC0) is 0 (not bidirectional mode), this
pin is the serial data output. When the SPI is enabled as a slave and SPC0 = 0, this pin is the serial data
input. If SPC0 = 1 to select single-wire bidirectional mode, and master mode is selected, this pin becomes
the bidirectional data I/O pin (MOMI). Also, the bidirectional mode output enable bit determines whether
the pin acts as an input (BIDIROE = 0) or an output (BIDIROE = 1). If SPC0 = 1 and slave mode is
selected, this pin is not used by the SPI and reverts to being a general-purpose port I/O pin.
13.2.3
When the SPI is enabled as a master and SPI pin control zero (SPC0) is 0 (not bidirectional mode), this
pin is the serial data input. When the SPI is enabled as a slave and SPC0 = 0, this pin is the serial data
output. If SPC0 = 1 to select single-wire bidirectional mode, and slave mode is selected, this pin becomes
the bidirectional data I/O pin (SISO) and the bidirectional mode output enable bit determines whether the
pin acts as an input (BIDIROE = 0) or an output (BIDIROE = 1). If SPC0 = 1 and master mode is selected,
this pin is not used by the SPI and reverts to being a general-purpose port I/O pin.
13.2.4
When the SPI is enabled as a slave, this pin is the low-true slave select input. When the SPI is enabled as
a master and mode fault enable is off (MODFEN = 0), this pin is not used by the SPI and reverts to being
a general-purpose port I/O pin. When the SPI is enabled as a master and MODFEN = 1, the slave select
output enable bit determines whether this pin acts as the mode fault input (SSOE = 0) or as the slave select
output (SSOE = 1).
278
External Signal Description
SPSCK — SPI Serial Clock
MOSI — Master Data Out, Slave Data In
MISO — Master Data In, Slave Data Out
SS — Slave Select
BUS CLOCK
SPPR2:SPPR1:SPPR0
1, 2, 3, 4, 5, 6, 7, or 8
Figure 13-4. SPI Baud Rate Generation
MC9S08DZ60 Series Data Sheet, Rev. 4
PRESCALER
DIVIDE BY
2, 4, 8, 16, 32, 64, 128, or 256
CLOCK RATE DIVIDER
SPR2:SPR1:SPR0
DIVIDE BY
Freescale Semiconductor
MASTER
SPI
BIT RATE