mc68hc908mr8 Freescale Semiconductor, Inc, mc68hc908mr8 Datasheet - Page 282

• Manufacturer Part Number: mc68hc908mr8
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Input/Output (I/O) Ports
14.3.2 Data Direction Register A
Technical Data
282
NOTE:
Data direction register A (DDRA) determines whether each port A pin is
an input or an output. Writing a logic 1 to a DDRA bit enables the output
buffer for the corresponding port A pin; a logic 0 disables the output
buffer.
Reset:
DDRA[6:0] — Data Direction Register A Bits
Avoid glitches on port A pins by writing to the port A data register before
changing data direction register A bits from 0 to 1.
Figure 14-4
dress:
Read:
Write:
Ad-
These read/write bits control port A data direction. Reset clears
DDRA[6:0], configuring all port A pins as inputs.
1 = Corresponding port A pin configured as output
0 = Corresponding port A pin configured as input
$0004
Bit 7
0
Figure 14-3. Data Direction Register A (DDRA)
shows the port A I/O logic.
Input/Output (I/O) Ports
= Unimplemented
DDRA6 DDRA5 DDRA4 DDRA3 DDRA2 DDRA1 DDRA0
6
0
5
0
4
0
3
0
MC68HC908MR8 — Rev 4.1
Freescale Semiconductor
2
0
1
0
Bit 0
0