S912XEG384J3VA Datasheet, PDF (116/1324 Pages) Freescale Semiconductor, Inc – MC9S12XEP100 Reference Manual Covers MC9S12XE Family

Chapter 2 Port Integration Module (S12XEPIMV1)
2.3.14 S12X_EBI ports Reduced Drive Register (RDRIV)
Address 0x000D (PRR)
Access: User read/write⁽¹⁾
7
6
R
0
RDPK
W
5
4
3
2
1
0
0
RDPE
RDPD
RDPC
RDPB
RDPA
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 2-12. S12X_EBI ports Reduced Drive Register (RDRIV)
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.
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 functionality does not take effect on the pins in emulation modes.
Table 2-15. RDRIV Register Field Descriptions
Field
7
RDPK
6-5
4
RDPE
3
RDPD
2
RDPC
Description
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 independent of the function
used on the pins. 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.
Reserved—
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 independent of the function
used on the pins. 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.
Port D reduced drive—Select reduced drive for outputs
This bit configures the drive strength of all output pins as either full or reduced independent of the function used on
the pins. 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.
Port C reduced drive—Select reduced drive for outputs
This bit configures the drive strength of all output pins as either full or reduced independent of the function used on
the pins. 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.
MC9S12XE-Family Reference Manual Rev. 1.25
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