MC68HC08AS32 Datasheet, PDF (193/394 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

Input/Output (I/O) Ports
Port C
READ DDRC ($0006)
WRITE DDRC ($0006)
RESET
WRITE PTC ($0002)
DDRCx
PTCx
PTCx
READ PTC ($0002)
Figure 15-9. Port C I/O Circuit
When bit DDRCx is a logic 1, reading address $0002 reads the PTCx
data latch. When bit DDRCx is a logic 0, 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 15-4 summarizes
the operation of the port C pins.
Table 15-4. Port C Pin Functions
DDRC PTC
Bit
Bit
I/O Pin
Mode
Accesses to
DDRC
Read/Write
Accesses to PTC
Read
Write
[7] = 0 PTC2 Input, Hi-Z
DDRC[7]
0
PTC2
[7] = 1 PTC2
0
X
Output,
MCLK
Input, Hi-Z
DDRC[7]
DDRC[4:0]
Data Latch
Pin
—
PTC[4:3, 1:0]⁽¹⁾
1
X
Output
DDRC[4:0] PTC[4:0]
PTC[4:3, 1:0]
X = Don’t Care
Hi-Z = High Impedance
1. Writing affects data register, but does not affect input.
MC68HC08AS32 — Rev. 3.0
MOTOROLA
Input/Output (I/O) Ports
Advance Information
193