S908QC16CDRE FREESCALE [Freescale Semiconductor, Inc], S908QC16CDRE Datasheet - Page 114

• Manufacturer Part Number: S908QC16CDRE
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Input/Output Ports (PORTS)
PTCPUE[3:0] — Port C Input Pullup Enable Bits
11.6 Port D
Port D is an 8-bit general purpose I/O port. Each port D pin can be configured to have an internal pullup
when used as an input port pin.
11.6.1 Port D Data Register
The port D data register (PTD) contains a data latch for each of the eight port D pins.
PTD[7:0] — Port D Data Bits
11.6.2 Data Direction Register D
Data direction register D (DDRD) determines whether each port D pin is an input or an output. Writing a
1 to a DDRD bit enables the output buffer for the corresponding port D pin; a 0 disables the output buffer.
114
Table 11-3
1. X = don’t care
2. I/O pin pulled to V
3. Writing affects data register, but does not affect input.
4. Hi-Z = high impedance
PTCPUE
These read/write bits are software programmable to enable pullup devices on port C pins
These read/write bits are software programmable. Data direction of each port D pin is under the control
of the corresponding bit in data direction register D. Reset has no effect on port D data.
Bit
X
1
0
1 = Corresponding port C pin configured to have internal pull if its DDRC bit is set to 0
0 = Pullup device is disconnected on the corresponding port C pin regardless of the state of its
DDRC bit.
summarizes the operation of the port C pins.
Reset:
Reset:
Read:
Write:
Read:
Write:
DDRC
Bit
0
0
1
DD
MC68HC908QC16 • MC68HC908QC8 • MC68HC908QC4 Data Sheet, Rev. 2
DDRD7
by internal pullup.
PTD7
Bit 7
Bit 7
0
PTC
X
Bit
X
X
(1)
Figure 11-14. Data Direction Register D (DDRD)
DDRD6
Figure 11-13. Port D Data Register (PTD)
PTD6
6
6
0
Input, Hi-Z
Input, V
Table 11-3. Port C Pin Functions
I/O Pin
Output
Mode
DDRD5
DD
PTD5
5
5
0
(2)
(4)
DDRD4
Unaffected by reset
PTD4
4
4
0
Accesses to DDRC
DDRC2–DDRC0
DDRC2–DDRC0
DDRC2–DDRC0
Read/Write
DDRD3
PTD3
3
3
0
DDRD2
PTD2
2
2
0
PTC3–PTC0
DDRD1
PTD1
Read
1
1
0
Pin
Pin
Accesses to PTC
Freescale Semiconductor
DDRD0
PTD0
Bit 0
Bit 0
0
PTC3–PTC0
PTC3–PTC0
PTC3–PTC0
Write
(3)
(3)