Advance Information MC68HC908MR16/MC68HC908MR32 — Rev. 4.0
314 Input/Output (I/O) Ports MOTOROLA
Input/Output (I/O) Ports
15.5 Port C
Port C is a 7-bit, general-purpose, bidirectional I/O port that shares two
of its pins with the analog-to-digital convertor module (ADC).
15.5.1 Port C Data Register
The port C data register (PTC) contains a data latch for each of the
seven port C pins.
PTC[6:0] — Port C Data Bits
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.
15.5.2 Data Direction Register C
Data direction register C (DDRC) determines whether each port C pin is
an input or an output. Writing a logic 1 to a DDRC bit enables the output
buffer for the corresponding port C pin; a logic 0 disables the output
buffer.
Address: $0002
Bit 7654321Bit 0
Read: 0 PTC6 PTC5 PTC4 PTC3 PTC2 PTC1 PTC0
Write: R
Reset: Unaffected by reset
R= Reserved
Figure 15-8. Port C Data Register (PTC)
Address: $0006
Bit 7654321Bit 0
Read: 0 DDRC6 DDRC5 DDRC4 DDRC3 DDRC2 DDRC1 DDRC0
Write: R
Reset:00000000
R= Reserved
Figure 15-9. Data Direction Register C (DDRC)