Chapter 2 Port Integration Module (S12XEP100PIMV1)
MC9S12XE-Family Reference Manual , Rev. 1.19
116
Freescale Semiconductor
2.3.14
S12X_EBI ports Reduced Drive Register (RDRIV)
This register is used to select reduced drive for the pins associated with the S12X_EBI ports A, B, C, D,
E, and K. If enabled, the pins drive at approx. 1/5 of the full drive strength. The reduced drive function is
independent of which function is being used on a particular pin.
The reduced drive functionality does not take effect on the pins in emulation modes.
Address 0x000D (PRR)
Access: User read/write
(1)
1. Read: Anytime. In emulation modes, read operations will return the data from the external bus, in all other modes the data source
is depending on the data direction value.
Write: Anytime. In emulation modes, write operations will also be directed to the external bus.
7
6
5
4
3
2
1
0
R
RDPK
0
0
RDPE
RDPD
RDPC
RDPB
RDPA
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 2-12. S12X_EBI ports Reduced Drive Register (RDRIV)
Table 2-15. RDRIV Register Field Descriptions
Field
Description
7
RDPK
Port K reduced drive
—Select reduced drive for outputs
This bit configures the drive strength of all Port K output pins as either full or reduced. If a pin is used as input this
bit has no effect.
1 Reduced drive selected (approx. 1/5 of the full drive strength).
0 Full drive strength enabled.
6-5
Reserved
—
4
RDPE
Port E reduced drive
—Select reduced drive for outputs
This bit configures the drive strength of all Port E output pins as either full or reduced. If a pin is used as input this
bit has no effect.
1 Reduced drive selected (approx. 1/5 of the full drive strength).
0 Full drive strength enabled.
3
RDPD
Port D reduced drive
—Select reduced drive for outputs
This bit configures the drive strength of all output pins as either full or reduced. If a pin is used as input this bit has
no effect.
1 Reduced drive selected (approx. 1/5 of the full drive strength).
0 Full drive strength enabled.
2
RDPC
Port C reduced drive
—Select reduced drive for outputs
This bit configures the drive strength of all output pins as either full or reduced. If a pin is used as input this bit has
no effect.
1 Reduced drive selected (approx. 1/5 of the full drive strength).
0 Full drive strength enabled.
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