s908gz60cfa Freescale Semiconductor, Inc, s908gz60cfa Datasheet - Page 179

• Manufacturer Part Number: s908gz60cfa
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

DDRC6–DDRC0 — Data Direction Register C Bits
Figure 13-11
When bit DDRCx is a 1, reading address $0002 reads the PTCx data latch. When bit DDRCx is a 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.
Freescale Semiconductor
1. X = Don’t care
2. I/O pin pulled up to V
3. Writing affects data register, but does not affect input.
4. Hi-Z = High impedance
PTCPUE
These read/write bits control port C data direction. Reset clears DDRC6–DDRC0, configuring all port
C pins as inputs.
Bit
1
0
X
1 = Corresponding port C pin configured as output
0 = Corresponding port C pin configured as input
shows the port C I/O logic.
DDRC
Avoid glitches on port C pins by writing to the port C data register before
changing data direction register C bits from 0 to 1.
Bit
0
0
1
MC68HC908GZ60 • MC68HC908GZ48 • MC68HC908GZ32 Data Sheet, Rev. 6
DD
READ DDRC ($0006)
WRITE DDRC ($0006)
WRITE PTC ($0002)
READ PTC ($0002)
by internal pullup device.
PTC
X
Bit
X
X
(1)
Input, Hi-Z
Input, V
Table 13-4. Port C Pin Functions
I/O Pin
Output
RESET
Mode
Figure 13-11. Port C I/O Circuit
DD
(2)
(4)
Table 13-4
NOTE
Accesses to DDRC
DDRCx
PTCx
DDRC6–DDRC0
DDRC6–DDRC0
DDRC6–DDRC0
Read/Write
summarizes the operation of the port C pins.
PTCPUEx
PTC6–PTC0
Read
Pin
Pin
Accesses to PTC
V
DD
INTERNAL
PULLUP
DEVICE
PTCx
PTC6–PTC0
PTC6–PTC0
PTC6–PTC0
Write
Port C
(3)
(3)
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