mc9s12xd256 Freescale Semiconductor, Inc, mc9s12xd256 Datasheet - Page 835

• Manufacturer Part Number: mc9s12xd256
• Description: Hcs12x Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

22.3.2.12 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.
Freescale Semiconductor
Reset
RDPK
RDPE
RDPD
RDPC
RDPB
RDPA
Field
7
4
3
2
1
0
W
R
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.
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.
0
7
= Unimplemented or Reserved
Figure 22-14. S12X_EBI Ports Reduced Drive Register (RDRIV)
0
0
6
Table 22-15. RDRIV Field Descriptions
MC9S12XDP512 Data Sheet, Rev. 2.17
0
0
5
RDPE
0
4
Description
Chapter 22 DP512 Port Integration Module (S12XDP512PIMV2)
RDPD
0
3
RDPC
0
2
RDPB
0
1
RDPA
0
0
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