MC68HC05P9A Datasheet, PDF (66/158 Pages) Freescale Semiconductor, Inc – HCMOS Microcontroller Unit

Parallel I/O Ports
Freescale Semiconductor, Inc.
Introduction
Twenty bidirectional pins and one input-only pin form four parallel
input/output (I/O) ports. All the bidirectional port pins are programmable
as inputs or outputs.
NOTE:
Connect any unused I/O pins to an appropriate logic level, either V_DD or
V_SS. Although the I/O ports do not require termination for proper
operation, termination reduces excess current consumption and the
possibility of electrostatic damage.
Addr.
$0000
Name:
R/W Bit 7 6
Port A Data Register (PORTA)
Read:
Write:
PA7
PA6
Reset:
5
4
3
2
PA5 PA4 PA3 PA2
Unaffected by reset
1 Bit 0
PA1 PA0
$0001
Port B Data Register (PORTB)
Read:
Write:
PB7
PB6
PB5
0
0
0
0
0
Reset:
Unaffected by reset
$0002
Port C Data Register (PORTC)
Read:
Write:
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
Reset:
Unaffected by reset
$0003
Port D Data Register (PORTD)
Read:
Write:
PD7
0
PD5
1
0
0
0
0
Reset:
Unaffected by reset
$0004
Data Direction Register A (DDRA)
Read:
Write:
DDRA7
DDRA6
DDRA5
DDRA4
DDRA3
DDRA2
DDRA1
DDRA0
Reset: 0
0
0
0
0
0
0
0
$0005
Data Direction Register B (DDRB)
Read:
Write:
DDRB7
DDRB6
DDRB5
0
0
0
0
0
Reset: 0
0
0
0
0
0
0
0
= Unimplemented
Figure 28. Parallel I/O Port Register Summary
6-mc68hc05p9a
66
Parallel I/O Ports
MOTOROLA
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