MC68HC908GZ8 FREESCALE [Freescale Semiconductor, Inc], MC68HC908GZ8 Datasheet - Page 249

• Manufacturer Part Number: MC68HC908GZ8
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

SPRF — SPI Receiver Full Bit
ERRIE — Error Interrupt Enable Bit
OVRF — Overflow Bit
MODF — Mode Fault Bit
SPTE — SPI Transmitter Empty Bit
Freescale Semiconductor
This clearable, read-only flag is set each time a byte transfers from the shift register to the receive data
register. SPRF generates a CPU interrupt request if the SPRIE bit in the SPI control register is set also.
During an SPRF CPU interrupt, the CPU clears SPRF by reading the SPI status and control register
with SPRF set and then reading the SPI data register.
Reset clears the SPRF bit.
This read/write bit enables the MODF and OVRF bits to generate CPU interrupt requests. Reset clears
the ERRIE bit.
This clearable, read-only flag is set if software does not read the byte in the receive data register before
the next full byte enters the shift register. In an overflow condition, the byte already in the receive data
register is unaffected, and the byte that shifted in last is lost. Clear the OVRF bit by reading the SPI
status and control register with OVRF set and then reading the receive data register. Reset clears the
OVRF bit.
This clearable, read-only flag is set in a slave SPI if the SS pin goes high during a transmission with
the MODFEN bit set. In a master SPI, the MODF flag is set if the SS pin goes low at any time with the
MODFEN bit set. Clear the MODF bit by reading the SPI status and control register (SPSCR) with
MODF set and then writing to the SPI control register (SPCR). Reset clears the MODF bit.
This clearable, read-only flag is set each time the transmit data register transfers a byte into the shift
register. SPTE generates an SPTE CPU interrupt request or an SPTE DMA service request if the
SPTIE bit in the SPI control register is set also.
During an SPTE CPU interrupt, the CPU clears the SPTE bit by writing to the transmit data register.
Reset sets the SPTE bit.
1 = Receive data register full
0 = Receive data register not full
1 = MODF and OVRF can generate CPU interrupt requests
0 = MODF and OVRF cannot generate CPU interrupt requests
1 = Overflow
0 = No overflow
1 = SS pin at inappropriate logic level
0 = SS pin at appropriate logic level
1 = Transmit data register empty
0 = Transmit data register not empty
Address: $0011
Do not write to the SPI data register unless the SPTE bit is high.
Reset:
Read:
Write:
Figure 17-15. SPI Status and Control Register (SPSCR)
SPRF
Bit 7
0
MC68HC908GZ16 • MC68HC908GZ8 Data Sheet, Rev. 4
= Unimplemented
ERRIE
6
0
OVRF
5
0
NOTE
MODF
4
0
SPTE
3
1
MODFEN
2
0
SPR1
1
0
SPR0
Bit 0
0
I/O Registers
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