mc9s12vr48 Freescale Semiconductor, Inc, mc9s12vr48 Datasheet - Page 357

• Manufacturer Part Number: mc9s12vr48
• Description: S12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

11.4
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:
Freescale Semiconductor
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Receive Shift Register
Receive Shift Register
Slave select (SS)
Serial clock (SCK)
Master out/slave in (MOSI)
Master in/slave out (MISO)
SPI Data Register
SPI Data Register
Functional Description
SPIF
SPIF
Data A Received
Data A Received
Figure 11-10. Reception with SPIF serviced too late
Figure 11-9. Reception with SPIF serviced in Time
= Unspecified
= Unspecified
MC9S12VR Family Reference Manual, Rev. 2.2
Preliminary - Subject to Change Without Notice
Data A
Data A
Data A
Data A
= Reception in progress
= Reception in progress
Data B Received
Data B Received
Data B
Data B
SPIF Serviced
Data B Lost
SPIF Serviced
Data B
Serial Peripheral Interface (S12SPIV5)
Data C Received
Data C Received
Data C
Data C
Data C
Data C
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