XC68HC705JJ7 Motorola, XC68HC705JJ7 Datasheet - Page 85

• Manufacturer Part Number: XC68HC705JJ7
• Description: MICROCONTROLLER
• Manufacturer: Motorola

7.3.1 Port A Data Register
MC68HC705JJ7 • MC68HC705JP7 — REV 4
MOTOROLA
The port A data register (PORTA) contains a bit for each of the port A
pins. When a port A pin is programmed to be an output, the state of its
data register bit determines the state of the output pin. When a port A pin
is programmed to be an input, reading the port A data register returns
the logic state of the pin. The upper two bits of the port A data register
will always read as logic 0s.
PA5–PA0 — Port A Data Bits
Alternate:
Address:
Reset:
These read/write bits are software programmable. Data direction of
each bit is under the control of the corresponding bit in the port A data
direction register (DDRA). Reset has no effect on port A data.
Read:
Write:
$0000
Bit 7
0
Figure 7-1. Port A Data Register (PORTA)
Parallel Input/Output
= Unimplemented
6
0
PA5
5
Unaffected by reset
PA4
4
KYBD3
PA3
3
KYBD2
PA2
2
Advance Information
Parallel Input/Output
KYBD1
PA1
1
KYBD0
Bit 0
PA0
Port A
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