MC9S12XD256MAL Datasheet, PDF (833/1348 Pages) Freescale Semiconductor, Inc – Freescale’s Scalable Controller Area Network

Chapter 22 DP512 Port Integration Module (S12XDP512PIMV2)
22.3.2.12 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 22-14. 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 are read from this register.
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 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 22-15. 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.
MC9S12XDP512 Data Sheet, Rev. 2.21
Freescale Semiconductor
835