MC68HC08AZ16 Datasheet, PDF (341/527 Pages) Motorola, Inc – HCMOS Microcontroller Unit

I/O Ports
Figure 18 shows the port F I/O logic.
READ DDRF ($000D)
WRITE DDRF ($000D)
RESET
WRITE PTF ($0009)
READ PTF ($0009)
DDRFx
PTFx
PTFx
Figure 18. Port F I/O circuit
When bit DDRFx is a logic one, reading address $0009 reads the PTFx
data latch. When bit DDRFx is a logic zero, reading address $0009
reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit. Table 7 summarizes the
operation of the port F pins.
Table 7. Port F pin functions
DDRF Bit
0
PTF Bit
X⁽¹⁾
I/O Pin Mode
Input, Hi-Z⁽²⁾
Accesses to
DDRF
Read/Write
DDRF[6:0]
1
X
Output
DDRF[6:0]
1. X = don’t care
2. Hi-Z = high impedance
3. Writing affects data register, but does not affect input.
Accesses to PTF
Read
Pin
PTF[6:0]
Write
PTF[6:0]⁽³⁾
PTF[6:0]
MC68HC08AZ32
340
I/O Ports
20-io
MOTOROLA