mc68hc912bc32 Freescale Semiconductor, Inc, mc68hc912bc32 Datasheet - Page 87

• Manufacturer Part Number: mc68hc912bc32
• Description: M68hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

6.3.3 Port B Data Register
Read: Anytime, if register is in the map
Write: Anytime, if register is in the map
Bits PB7–PB0 are associated with addresses ADDR7–ADDR0 and DATA7–DATA0. When port B is not
used for external addresses and data such as in single-chip mode, these pins can be used as
general-purpose I/O. DDRB determines the primary direction of each pin. This register is not in the
on-chip map in expanded and peripheral modes.
6.3.4 Port B Data Direction Register
Read: Anytime, if register is in the map
Write: Anytime, if register is in the map
This register determines the primary direction for each port B pin when functioning as a general-purpose
I/O port. DDRB is not in the on-chip map in expanded and peripheral modes.
Freescale Semiconductor
Expanded wide and peripheral:
1 = Associated pin is an output.
0 = Associated pin is a high-impedance input.
Address: $0003
Alternate functions:
Expanded narrow:
Reset:
Read:
Write:
Address: $0001
Reset:
DDB7
Read:
Write:
Bit 7
0
Figure 6-4. Port B Data Direction Register (DDRB)
ADDR7
ADDR7
DATA7
Figure 6-3. Port B Data Register (PORTB)
Bit 7
PB7
DDB6
6
0
M68HC12B Family Data Sheet, Rev. 9.1
ADDR6
ADDR6
DATA6
PB6
DDB5
6
5
0
ADDR5
ADDR5
DATA5
PB5
DDB4
5
4
0
ADDR4
DATA4
ADDR4
Unaffected by reset
PB4
DDB3
4
3
0
ADDR3
ADDR3
DATA3
PB3
DDB2
3
2
0
ADDR2
ADDR2
DATA2
PB2
DDB1
2
1
0
ADDR1
ADDR1
DATA1
PB1
DDB0
1
Bit 0
0
ADDR0
ADDR0
DATA0
Bit 0
PB0
Registers
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