
Parallel Input/Output (I/O) Ports
Port A
MC68HC11E Family
—
Rev. 4
Technical Data
MOTOROLA
Parallel Input/Output (I/O) Ports
135
DDRA7
—
Data Direction for Port A Bit 7
Overridden if an output compare function is configured to control the
PA7 pin
0 = Input
1 = Output
The pulse accumulator uses port A bit 7 as the PAI input, but the pin
can also be used as general-purpose I/O or as an output compare.
NOTE:
Even when port A bit 7 is configured as an output, the pin still drives the
input to the pulse accumulator.
PAEN
—
Pulse Accumulator System Enable Bit
Refer to
Section 9. Timing System
.
PAMOD
—
Pulse Accumulator Mode Bit
Refer to
Section 9. Timing System
.
PEDGE
—
Pulse Accumulator Edge Control Bit
Refer to
Section 9. Timing System
.
DDRA3
—
Data Direction for Port A Bit 3
This bit is overridden if an output compare function is configured to
control the PA3 pin.
0 = Input
1 = Output
I4/O5
—
Input Capture 4/Output Compare 5 Bit
Refer to
Section 9. Timing System
.
RTR[1:0]
—
RTI Interrupt Rate Select Bits
Refer to
Section 9. Timing System
.
Address:
$1026
Bit 7
6
5
4
3
2
1
Bit 0
Read:
DDRA7
PAEWN
PAMOD
PEDGE
DDRA3
I4/O5
RTR1
RTR0
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 6-2. Pulse Accumulator Control Register (PACTL)