s908gr16ag4cfj Freescale Semiconductor, Inc, s908gr16ag4cfj Datasheet - Page 126

• Manufacturer Part Number: s908gr16ag4cfj
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

Input/Output (I/O) Ports
Figure 12-15
When bit DDRDx is a 1, reading address $0003 reads the PTDx data latch. When bit DDRDx is a 0,
reading address $0003 reads the voltage level on the pin. The data latch can always be written,
regardless of the state of its data direction bit.
126
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
PTDPUE
Bit
X
1
0
shows the port D I/O logic.
DDRD
Bit
0
0
1
DD
READ DDRD ($0007)
WRITE DDRD ($0007)
WRITE PTD ($0003)
READ PTD ($0003)
by internal pullup device.
PTD
X
Bit
X
X
(1)
Input, Hi-Z
Input, V
MC68HC908GR16A Data Sheet, Rev. 1.0
Table 12-5. Port D Pin Functions
RESET
Figure 12-15. Port D I/O Circuit
I/O Pin
Output
Mode
DD
(2)
(4)
Table 12-5
Accesses to DDRD
DDRDx
PTDx
DDRD7–DDRD0
DDRD7–DDRD0
DDRD7–DDRD0
Read/Write
summarizes the operation of the port D pins.
PTDPUEx
PTD7–PTD0
Read
Pin
Pin
Accesses to PTD
V
DD
Freescale Semiconductor
INTERNAL
PULLUP
DEVICE
PTDx
PTD7–PTD0
PTD7–PTD0
PTD7–PTD0
Write
(3)
(3)