mc68hc908jb8 Freescale Semiconductor, Inc, mc68hc908jb8 Datasheet - Page 208

• Manufacturer Part Number: mc68hc908jb8
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Input/Output Ports (I/O)
12.5.2 Data Direction Register C
Technical Data
208
NOTE:
NOTE:
Address:
Data direction register C 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.
DDRC[7:0] — Data Direction Register C Bits
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.
For those devices packaged in a 20-pin PDIP, 20-pin SOIC, and 28-pin
SOIC package, PTC7–PTC1 are not connected. DDRC7–DDRC1
should be set to a 1 to configure PTC7–PTC1 as outputs.
Figure 12-10
Reset:
Read:
Write:
These read/write bits control port C data direction. Reset clears
DDRC[7:0], configuring all port C pins as inputs.
1 = Corresponding port C pin configured as output
0 = Corresponding port C pin configured as input
DDRC7
$0006
Bit 7
0
Figure 12-9. Data Direction Register C (DDRC)
shows the port C I/O logic.
Input/Output Ports (I/O)
DDRC6
6
0
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3
DDRC5
5
0
DDRC4
4
0
DDRC3
3
0
DDRC2
Freescale Semiconductor
0
2
DDRC1
0
1
DDRC0
Bit 0
0