Motorola MC68HC908AB32 - SPI Module Block Diagram

Serial Peripheral Interface Module (SPI)
Technical Data MC68HC908AB32 — Rev. 1.0
282 Serial Peripheral Interface Module (SPI) MOTOROLA
Figure 16-2. SPI Module Block Diagram
The SPI module allows full-duplex, synchronous, serial communication
between the MCU and peripheral devices, including other MCUs.
Software can poll the SPI status flags or SPI operation can be interrupt-
driven.
The following paragraphs describe the operation of the SPI module.
TRANSMITTER CPU INTERRUPT REQUEST
RESERVED
RECEIVER/ERROR CPU INTERRUPT REQUEST
76543210
SPR1
SPMSTR
TRANSMIT DATA REGISTER
SHIFT REGISTER
SPR0
CGMOUT ÷ 2
CLOCK
SELECT
÷ 2
CLOCK
DIVIDER
÷ 8
÷ 32
÷ 128
CLOCK
LOGIC
CPHA CPOL
SPI
SPRIE
R
SPE
SPWOM
SPRF
SPTE
OVRF
RESERVED
M
S
PIN
CONTROL
LOGIC
RECEIVE DATA REGISTER
SPTIE
SPE
INTERNAL BUS
FROM SIM
MODFEN
ERRIE
CONTROL
MODF
SPMSTR
MOSI
MISO
SPSCK
SS