Serial Peripheral Interface (S12SPIV5)
S12XS Family Reference Manual, Rev. 1.13
Freescale Semiconductor
447
Figure 15-9. Reception with SPIF serviced in Time
Figure 15-10. Reception with SPIF serviced too late
15.4
Functional Description
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or SPI operation can be interrupt driven.
The SPI system is enabled by setting the SPI enable (SPE) bit in SPI control register 1. While SPE is set,
the four associated SPI port pins are dedicated to the SPI function as:
•
Slave select (SS)
•
Serial clock (SCK)
•
Master out/slave in (MOSI)
•
Master in/slave out (MISO)
Receive Shift Register
SPIF
SPI Data Register
Data A
Data B
Data A
Data A Received
Data B Received
Data C
Data C
SPIF Serviced
Data C Received
Data B
= Unspecified
= Reception in progress
Receive Shift Register
SPIF
SPI Data Register
Data A
Data B
Data A
Data A Received
Data B Received
Data C
Data C
SPIF Serviced
Data C Received
Data B Lost
= Unspecified
= Reception in progress
Summary of Contents for MC9S12XS128
Page 4: ...S12XS Family Reference Manual Rev 1 13 4 Freescale Semiconductor ...
Page 168: ...Interrupt S12XINTV2 S12XS Family Reference Manual Rev 1 13 168 Freescale Semiconductor ...
Page 736: ...Ordering Information S12XS Family Reference Manual Rev 1 13 736 Freescale Semiconductor ...
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