MC68HC08AZ16 Datasheet, PDF (331/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

I/O Ports
READ DDRC ($0006)
WRITE DDRC ($0006)
RESET
WRITE PTC ($0002)
.
DDRCx
PTCx
PTCx
READ PTC ($0002)
Figure 9. Port C I/O circuit
When bit DDRCx is a logic one, reading address $0002 reads the PTCx
data latch. When bit DDRCx is a logic zero, reading address $0002
reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit. Table 4 summarizes the
operation of the port C pins.
Table 4. Port C pin functions
Bit Value
PTC Bit
I/O Pin Mode
Accesses to
DDRC
Read/Write
0
2
Input, Hi-Z
DDRC[7]
1
2
Output
DDRC[7]
0
X⁽¹⁾
Input, Hi-Z⁽²⁾ DDRC[5:0]
1
X
Output
DDRC[5:0]
1. X = don’t care
2. Hi-Z = high impedance
3. Writing affects data register, but does not affect input.
Accesses to PTC
Read
Pin
0
Pin
PTC[5:0]
Write
PTC2
—
PTC[5:0]⁽³⁾
PTC[5:0]
MC68HC08AZ32
330
I/O Ports
10-io
MOTOROLA