MC68HC05L28B MOTOROLA [Motorola, Inc], MC68HC05L28B Datasheet - Page 47

• Manufacturer Part Number: MC68HC05L28B
• Description: Flexible general-purpose microcomputer
• Manufacturer: MOTOROLA [Motorola, Inc]

4.4.1
Each bit can be configured as input or output via the corresponding data direction bit in the port
data direction register (DDRx).
Reset does not affect the state of the port data registers.
Each of the port D bits is shared with another MCU subsystem. The configuration of this register
is determined by the setting of individual bits in the port D control register. See Section 4.4.3.
4.4.2
Writing a ‘1’ to any bit configures the corresponding port pin as an output; conversely, writing any
bit to ‘0’ configures the corresponding port pin as an input.
Reset clears these registers, thus configuring all ports as inputs.
4.4.3
The select register, data direction register and control register determine the function of the I/O
port, as shown in Table 4-2.
MC68HC05L28
Port D data direction (DDRD)
Port A data direction (DDRA)
Port B data direction (DDRB)
Port D control (COND)
Port D data (PORTD)
Port B data (PORTB)
Port A data (PORTA)
Port data registers (PORTA, PORTB and PORTD)
Data direction registers (DDRA, DDRB and DDRD)
Port D control register (COND)
Address
Address
Address
$0000
$0001
$0030
$0032
$0004
$0005
$0031
INPUT/OUTPUT PORTS
bit 7
bit 7
bit 7
bit 6
bit 6
bit 6
bit 5
bit 5
bit 5
bit 4
bit 4
bit 4
bit 3
bit 3
bit 3
bit 2
bit 2
bit 2
bit 1
bit 1
bit 1
bit 0
bit 0
bit 0
MOTOROLA
Unaffected
Unaffected
0000 0000
0000 0000
Unaffected
0000 0000
0000 0000
on reset
on reset
on reset
State
State
State
TPG
4-3
4