MC9S12XD256MAL Datasheet, PDF (925/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

23.0.5.12 S12X_EBI Ports Reduced Drive Register (RDRIV)
R
W
Reset
7
RDPK
0
6
5
4
3
2
1
0
0
RDPE
RDPD
RDPC
RDPB
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 23-14. S12X_EBI Ports Reduced Drive Register (RDRIV)
0
RDPA
0
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 ports A, B, E, and K. If
enabled, the pins drive at about 1/6 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.
Table 23-15. RDRIV Field Descriptions
Field
7
RDPK
4
RDPE
3
RDPD
2
RDPC
1
RDPB
0
RDPA
Description
Reduced Drive of Port K
0 All port K output pins have full drive enabled.
1 All port K output pins have reduced drive enabled.
Reduced Drive of Port E
0 All port E output pins have full drive enabled.
1 All port E output pins have reduced drive enabled.
Reduced Drive of Port D
0 All port D output pins have full drive enabled.
1 All port D output pins have reduced drive enabled.
Reduced Drive of Port C
0 All port C output pins have full drive enabled.
1 All port C output pins have reduced drive enabled.
Reduced Drive of Port B
0 All port B output pins have full drive enabled.
1 All port B output pins have reduced drive enabled.
Reduced Drive of Ports A
0 All Port A output pins have full drive enabled.
1 All port A output pins have reduced drive enabled.