mc68hc912bc32 Freescale Semiconductor, Inc, mc68hc912bc32 Datasheet - Page 205

• Manufacturer Part Number: mc68hc912bc32
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

SPE — SPI System Enable Bit
SWOM — Port S Wired-OR Mode Bit
MSTR — SPI Master/Slave Mode Select Bit
CPOL and CPHA — SPI Clock Polarity, Clock Phase Bits
SSOE — Slave Select Output Enable Bit
LSBF — SPI LSB First Enable Bit
14.3.5.2 SPI Control Register 2
Read: Anytime
Write: Anytime
PUPS — Pullup Port S Enable Bit
RDS — Reduce Drive of Port S Bit
Freescale Semiconductor
When MODF is set, SPE always reads 0. SP0CR1 must be written as part of a mode fault recovery
sequence.
Controls not only SPI output pins but also the general-purpose output pins (PS4–PS7) which are not
used by SPI.
These two bits are used to specify the clock format to be used in SPI operations. When the clock
polarity bit is cleared and data is not being transferred, the SCK pin of the master device is low. When
CPOL is set, SCK idles high. See
The SS output feature is enabled only in master mode by asserting the SSOE and DDS7.
Normally, data is transferred MSB first. This bit does not affect the position of the MSB and LSB in the
data register. Reads and writes of the data register always have MSB in bit 7.
0 = SPI internal hardware is initialized and SPI system is in a low-power disabled state.
1 = PS4–PS7 are dedicated to the SPI function.
0 = SPI and/or PS4–PS7 output buffers operate normally.
1 = SPI and/or PS4–PS7 output buffers behave as open-drain outputs.
0 = Slave mode
1 = Master mode
0 = Data is transferred most-significant bit (MSB) first.
1 = Data is transferred least-significant bit (LSB) first.
0 = No internal pullups on port S
1 = All port S input pins have an active pullup device. If a pin is programmed as output, the pullup
0 = Port S output drivers operate normally.
1 = All port S output pins have reduced drive capability for lower power and less noise.
device becomes inactive.
Address:
Reset:
Read:
Write:
$00D1
Bit 7
0
0
Figure 14-16. SPI Control Register 2 (SP0CR2)
= Unimplemented
M68HC12B Family Data Sheet, Rev. 9.1
6
0
0
Figure 14-12
5
0
0
and
4
0
0
Figure
PUPS
14-13.
3
1
RDS
2
0
Serial Peripheral Interface (SPI)
1
0
0
SPC0
Bit 0
0
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