Chapter 2 Port Integration Module (S12XEP100PIMV1)
MC9S12XE-Family Reference Manual , Rev. 1.19
Freescale Semiconductor
179
2.4.2.1
Data register (PORTx, PTx)
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
Input register (PTIx)
This is a read-only register and always returns the buffered state of the pin (
2.4.2.3
Data direction register (DDRx)
This register defines whether the pin is used as an input or an output.
If a peripheral module controls the pin the contents of the data direction register is ignored (
Table 2-103. Register availability per port
(1)
1. Each cell represents one register with individual configuration bits
Port
Data
Input
Data
Direction
Reduced
Drive
Pull
Enable
Polarity
Select
Wired-
Or Mode
Interrupt
Enable
Interrupt
Flag
Routing
A
yes
-
yes
yes
yes
-
-
-
-
-
B
yes
-
yes
-
-
-
-
-
C
yes
-
yes
-
-
-
-
-
D
yes
-
yes
-
-
-
-
-
E
yes
-
yes
-
-
-
-
-
K
yes
-
yes
-
-
-
-
-
T
yes
yes
yes
yes
yes
yes
-
-
-
-
S
yes
yes
yes
yes
yes
yes
yes
-
-
yes
M
yes
yes
yes
yes
yes
yes
yes
-
-
yes
P
yes
yes
yes
yes
yes
yes
-
yes
yes
-
H
yes
yes
yes
yes
yes
yes
-
yes
yes
-
J
yes
yes
yes
yes
yes
yes
-
yes
yes
-
AD0
yes
-
yes
yes
yes
-
-
-
-
-
AD1
yes
-
yes
yes
yes
-
-
-
-
-
R
yes
yes
yes
yes
yes
yes
-
-
-
-
L
yes
yes
yes
yes
yes
yes
yes
-
-
yes
F
yes
yes
yes
yes
yes
yes
-
-
-
yes
Because
of
an
order
from
the
United
States
International
Trade
Commission,
BGA-packaged
product
lines
and
part
numbers
indicated
here
currently
are
not
available
from
Freescale
for
import
or
sale
in
the
United
States
prior
to
September
2010:
S12XE
products
in
208
MAPBGA
packages