Datasheet

Multiple Serial Interface
Technical Data MC68HC912DT128A — Rev 4.0
296 Multiple Serial Interface MOTOROLA
Read or write anytime.
PUPS — Pull-Up Port S Enable
0 = No internal pull-ups on port S
1 = All port S input pins have an active pull-up device. If a pin is
programmed as output, the pull-up device becomes inactive
RDPS — Reduce Drive of Port S
0 = Port S output drivers operate normally
1 = All port S output pins have reduced drive capability for lower
power and less noise
SSWAI — Serial Interface Stop in WAIT mode
0 = Serial interface clock operates normally
1 = Halt serial interface clock generation in WAIT mode
SPC0 — Serial Pin Control 0
This bit decides serial pin configurations with MSTR control bit.
SP0CR2 — SPI Control Register 2 $00D1
Bit 7654321Bit 0
0 0 0 0 PUPS RDPS SSWAI SPC0
RESET: 0 0 0 0 1 0 0 0
Pin Mode
SPC0
(1)
1. The serial pin control 0 bit enables bidirectional configurations.
MSTR
MISO
(2)
2. Slave output is enabled if DDRS4 = 1, SS = 0 and MSTR = 0. (#1, #3)
MOSI
(3)
3. Master output is enabled if DDRS5 = 1 and MSTR = 1. (#2, #4)
SCK
(4)
4. SCK output is enabled if DDRS6 = 1 and MSTR = 1. (#2, #4)
SS
(5)
5. SS output is enabled if DDRS7 = 1, SSOE = 1 and MSTR = 1. (#2, #4)
#1
Normal 0
0 Slave Out Slave In SCK In SS In
#2 1 Master In
Master
Out
SCK Out SS I/O
#3
Bidirectional 1
0 Slave I/O GPI/O SCK In SS In
#4 1 GPI/O Master I/O SCK Out SS I/O
Frees
cale Semiconductor,
I
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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