mc9s12xs128 Freescale Semiconductor, Inc, mc9s12xs128 Datasheet - Page 121

• Manufacturer Part Number: mc9s12xs128
• Description: Hcs12 Microcontrollers 16-bit Automotive Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

2.4.2
A set of configuration registers is common to all ports with exception of the ATD port
registers can be written at any time, however a specific configuration might not become active.
For example selecting a pull-up device: This device does not become active while the port is used as a
push-pull output.
1
2.4.2.1
This register holds the value driven out to the pin if the pin is used as a general purpose I/O.
Writing to this register has only an effect on the pin if the pin is used as general purpose output. When
reading this address, the buffered state of the pin is returned if the associated data direction register bit is
set to “0”.
If the data direction register bits are set to logic level “1”, the contents of the data register is returned. This
is independent of any other configuration
2.4.2.2
This is a read-only register and always returns the buffered state of the pin
2.4.2.3
This register defines whether the pin is used as a input or an output.
If a peripheral module controls the pin the contents of the data direction register is ignored
Independent of the pin usage with a peripheral module this register determines the source of data when
reading the associated data register address (2.4.2.1/2-121).
Freescale Semiconductor
Port
Each cell represents one register with individual configuration bits
AD
M
H
A
B
E
K
T
S
P
J
Data
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
Registers
Data register (PORTx, PTx)
Input register (PTIx)
Data direction register (DDRx)
Input
yes
yes
yes
yes
yes
yes
-
-
-
-
-
Direction
Data
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
yes
Table 2-71. Register availability per port
S12XS Family Reference Manual, Rev. 1.10
Reduced
Drive
yes
yes
yes
yes
yes
yes
yes
yes
(Figure
Enable
Pull
yes
yes
yes
yes
yes
yes
yes
yes
2-73).
Polarity
Select
yes
yes
yes
yes
yes
yes
-
-
-
-
-
Or Mode
Wired-
yes
yes
-
-
-
-
-
-
-
-
-
1
Port Integration Module (S12XSPIMV1)
(Figure
Interrupt
Enable
yes
yes
yes
-
-
-
-
-
-
-
-
2-73).
Interrupt
(Table
Flag
yes
yes
yes
-
-
-
-
-
-
-
-
(Figure
2-71). All
Routing
yes
yes
2-73).
-
-
-
-
-
-
-
-
-
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