MC68HC08AZ60ACFU MOTOROLA [Motorola, Inc], MC68HC08AZ60ACFU Datasheet - Page 268

• Manufacturer Part Number: MC68HC08AZ60ACFU
• Description: Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

Serial Peripheral Interface (SPI)
17.9 Resetting the SPI
Advance Information
268
Any system reset completely resets the SPI. Partial resets occur
whenever the SPI enable bit (SPE) is low. Whenever SPE is low, the
following occurs:
The following items are reset only by a system reset:
By not resetting the control bits when SPE is low, the user can clear SPE
between transmissions without having to set all control bits again when
SPE is set back high for the next transmission.
By not resetting the SPRF, OVRF, and MODF flags, the user can still
service these interrupts after the SPI has been disabled. The user can
disable the SPI by writing ‘0’ to the SPE bit. The SPI can also be disabled
by a mode fault occurring in an SPI that was configured as a master with
the MODFEN bit set.
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The SPTE flag is set
Any transmission currently in progress is aborted
The shift register is cleared
The SPI state counter is cleared, making it ready for a new
complete transmission
All the SPI port logic is defaulted back to being general purpose
I/O.
All control bits in the SPCR register
All control bits in the SPSCR register (MODFEN, ERRIE, SPR1,
and SPR0)
The status flags SPRF, OVRF, and MODF
Serial Peripheral Interface (SPI)
MC68HC08AZ60A — Rev 0.0
MOTOROLA