MC68HC908GT16 Datasheet, PDF (237/412 Pages) Motorola, Inc – Microcontrollers

Input/Output (I/O) Ports
Port C
16.5.2 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:
Read:
Write:
Reset:
$0006
Bit 7
0
6
5
4
3
2
1
DDRC6 DDRC5 DDRC4 DDRC3 DDRC2 DDRC1
0
0
0
0
0
0
0
= Unimplemented
Figure 16-10. Data Direction Register C (DDRC)
Bit 0
DDRC0
0
DDRC6–DDRC0 — Data Direction Register C Bits
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
NOTE: 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.
Figure 16-11 shows the port C I/O logic.
NOTE:
For those devices packaged in a 42-pin shrink dual in-line package,
PTC5 and PTC6 are connected to ground internally. DDRC5 and
DDRC6 should be set to a 0 to configure PTC5 and PTC6 as inputs.
MC68HC908GT16 • MC68HC908GT8 — Rev. 2
MOTOROLA
Input/Output (I/O) Ports
Technical Data
237