Chapter 4 Port Integration Module (S12XDP512PIMV2)
MC9S12XDP512 Data Sheet, Rev. 2.11
Freescale Semiconductor 207
4.3.2.12 S12X_EBI Ports Reduced Drive Register (RDRIV)
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.

0x000D (PRR)
76543210
R
RDPK
00
RDPE RDPD RDPC RDPB RDPA
W
Reset 00000000
= Unimplemented or Reserved

Figure 4-14. S12X_EBI Ports Reduced Drive Register (RDRIV)

Table 4-15. RDRIV Field Descriptions

Field Description
7
RDPK
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.
4
RDPE
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.
3
RDPD
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.
2
RDPC
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.
1
RDPB
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.
0
RDPA
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.