MC68HC11KA4TS Datasheet, PDF (45/68 Pages) Motorola, Inc – 8-Bit Microcontroller

SPCR —Serial Peripheral Control Register
$0028
RESET:
Bit 7
SPIE
0
6
SPE
0
5
DWOM
0
4
MSTR
0
3
CPOL
0
2
CPHA
1
1
SPR1
U
Bit 0
SPR0
U
SPIE — Serial Peripheral Interrupt Enable
0 = SPI interrupts disabled
1 = SPI interrupts enabled
SPE — Serial Peripheral System Enable
0 = SPI off
1 = SPI on
DWOM — Port D Wired-OR Mode Option for SPI Pins PD[5:2] (See also WOMS bit in SCCR1.)
0 = Normal CMOS outputs
1 = Open-drain outputs
MSTR — Master Mode Select
0 = Slave mode
1 = Master mode
CPOL, CPHA — Clock Polarity, Clock Phase
Refer to SPI Transfer Format.
SCK CYCLE #
SCK (CPOL = 0)
1
2
3
4
5
6
7
8
SCK (CPOL = 1)
SAMPLE INPUT
(CPHA = 0) DATA OUT
SAMPLE INPUT
(CPHA = 1) DATA OUT
SS (TO SLAVE)
MSB
6
MSB
3
2
1
1. SS ASSERTED
2. MASTER WRITES TO SPDR
3. FIRST SCK EDGE
4. SPIF SET
5. SS NEGATED
5
4
3
2
1
6
5
4
3
2
SLAVE CPHA=1 TRANSFER IN PROGRESS
MASTER TRANSFER IN PROGRESS
SLAVE CPHA=0 TRANSFER IN PROGRESS
LSB
1
Figure 13 SPI Transfer Format
LSB
4
5
SPI TRANSFER FORMAT 1
MC68HC11KA4
MC68HC11KA4TS/D
MOTOROLA
45