MC68HC912B32
MC68HC912B32TS/D
MOTOROLA
97
DDS0 — Data Direction for Port S Bit 2 and Bit 0
If the SCI receiver is configured for two-wire SCI operation, corresponding port S pins will be input re-
gardless of the state of these bits.
DDS1 — Data Direction for Port S Bit 1
If the SCI transmitter is configured for two-wire SCI operation, corresponding port S pins will be output
regardless of the state of these bits.
DDS2, DDRS3 — Data Direction for Port S Bit 2 and Bit 3
These bits are for general-purpose I/O only.
DDS[6:4] — Data Direction for Port S Bits 6 through 4
If the SPI is enabled and expects the corresponding port S pin to be an input, it will be an input regard-
less of the state of the DDRS bit. If the SPI is enabled and expects the bit to be an output, it will be an
output only if the DDRS bit is set.
DDS7 — Data Direction for Port S Bit 7
In SPI slave mode, DDS7 has no meaning or effect; the PS7 pin is dedicated as the SS input. In SPI
master mode, DDS7 determines whether PS7 is an error detect input to the SPI or a general-purpose
or slave select output line.
Read or write anytime.
RDPS2 — Reduce Drive of PS[7:4]
0 = Port S output drivers for bits 7 through 4 operate normally.
1 = Port S output pins for bits 7 through 4 have reduced drive capability for lower power and less
noise.
RDPS1 — Reduce Drive of PS[3:2]
0 = Port S output drivers for bits 3 and 2 operate normally.
1 = Port S output pins for bits 3 and 2 have reduced drive capability for lower power and less noise.
RDPS0 — Reduce Drive of PS[1:0]
0 = Port S output drivers for bits 1 and 0 operate normally.
1 = Port S output pins for bits 1 and 0 have reduced drive capability for lower power and less noise.
PUPS2 — Pull-Up Port S Enable PS[7:4]
0 = No internal pull-ups on port S bits 7 through 4.
1 = Port S input pins for bits 7 through 4 have an active pull-up device. If a pin is programmed as
output, the pull-up device becomes inactive.
PUPS1 — Pull-Up Port S Enable PS[3:2]
0 = No internal pull-ups on port S bits 3 and 2.
1 = Port S input pins for bits 3 and 2 have an active pull-up device. If a pin is programmed as output,
the pull-up device becomes inactive.
PUPS0 — Pull-Up Port S Enable PS[1:0]
0 = No internal pull-ups on port S bits 1 and 0.
1 = Port S input pins for bits 1 and 0 have an active pull-up device. If a pin is programmed as output,
the pull-up device becomes inactive.
PURDS
— Pull-Up and Reduced Drive for Port S
$00DB
Bit 7
6
5
4
3
2
1
Bit 0
0
RDPS2
RDPS1
RDPS0
0
PUPS2
PUPS1
PUPS0
RESET:
0
0
0
0
0
1
1
1