MC908GR16ACFA FREESCALE [Freescale Semiconductor, Inc], MC908GR16ACFA Datasheet - Page 122

• Manufacturer Part Number: MC908GR16ACFA
• Description: M68HC08 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Input/Output (I/O) Ports
12.4 Port C
Port C is a 7-bit, general-purpose bidirectional I/O port. Port C also has software configurable pullup
devices if configured as an input port.
12.4.1 Port C Data Register
The port C data register (PTC) contains a data latch for each of the seven port C pins.
PTC6–PTC0 — Port C Data Bits
12.4.2 Data Direction Register C
Data direction register C (DDRC) determines whether each port C pin is an input or an output. Writing a 1
to a DDRC bit enables the output buffer for the corresponding port C pin; a 0 disables the output buffer.
DDRC6–DDRC0 — Data Direction Register C Bits
122
These read/write bits are software-programmable. Data direction of each port C pin is under the control
of the corresponding bit in data direction register C. Reset has no effect on port C data.
These read/write bits control port C data direction. Reset clears DDRC6–DDRC0, configuring all port
C pins as inputs.
1 = Corresponding port C pin configured as output
0 = Corresponding port C pin configured as input
Address:
Address:
Avoid glitches on port C pins by writing to the port C data register before
changing data direction register C bits from 0 to 1.
Reset:
Read:
Write:
Reset:
Read:
Write:
$0002
Bit 7
$0006
Bit 7
1
0
0
Figure 12-10. Data Direction Register C (DDRC)
= Unimplemented
= Unimplemented
Figure 12-9. Port C Data Register (PTC)
PTC6
DDRC6
6
6
0
MC68HC908GR16A Data Sheet, Rev. 1.0
PTC5
DDRC5
5
5
0
NOTE
Unaffected by reset
PTC4
DDRC4
4
4
0
PTC3
DDRC3
3
3
0
PTC2
DDRC2
2
2
0
PTC1
DDRC1
1
1
0
Freescale Semiconductor
PTC0
DDRC0
Bit 0
Bit 0
0